Spread the word to help families get water filters

 Abby's SDG project has a focus on the quality of water in the U.S. Nitrates get into our drinking water and can run the risk of harming babies, in particular, when their formula uses tap water. Abby will be raising money to help struggling families afford filters for their drinking water. Help get the word out! Watch Abby's informational video, and help push out this message and offer. One can also donate money to Abby so she can help as many families as possible. Thanks! 

Learn about Solar Energy and what some new advancements are looking like

 One of our senior groups looked at solar energy and where it is at. Check out their website that makes things more understandable! 

Mental Health information in Evanstonian

 Thank you to Zachary for leading the effort for two articles in the Dec. 14 Evanstonian. One is an in-depth look at the conditions for ETHS, which are in line with national statistics for student mental health and well being, and the fact that nearly every indicator for mental health issues has been increasing the last decade for teens (depression, anxiety, suicides, etc.). It also summarizes some of the efforts being done by ETHS and views from students and staff alike. 

There is a letter from the editors outlining student thoughts about what more must be done by the school and community to help students. There is also a podcast link about this issue on this page. These are all wonderful efforts in line with SDG #3, Health and Well-being around the world! 

FreeRice.com, help fight extreme hunger around the world

 Check out FreeRice.com, where answering any question in numerous categories will donate, through the United Nations, 5 grains of rice to areas of extreme poverty and hunger. Help the hundreds of millions of people who are suffer from extreme hunger by playing this game...and you will even learn some new things, too!  

Oceanawarenessproject: Check it out on Tik Tok

 Check out Karlo's Tik Tok site, oceanawarenessproject. He set this up for his U.N. SDG project, and you and friends can learn some fascinating information about our oceans, and why it is imperative we respect them and maintain them. See why in the first couple weeks he has hundreds of followers and over 100,000 views! 

3-D and Augmented Reality sites to check out

 Some really interesting sites to explore both for fun and for future work and projects, the 3-D and Augmented Reality (AR) features Google is developing are really becoming amazing! 

Google Arts & Culture  AR site

Google Poly  3D site (although shutting down June 30, 2021)

Using STEM to help solve problems in your community - Samsung competition

 The Samsung Solve for Tomorrow competition gives up to $100,000 to schools and students who have wonderful STEM solutions for problems in their communities. Check it out and see if there is something you and/or a group of students could do! Why not?!?! 

See 15 other examples of what some teens are doing around the country to help change the world for the better! 

FlashMob Orchestra - Just Enjoy! We will see things like this again!

 Just enjoy, and smile!! 

Arctic has changed dramatically in last 15 years

 Check out this Washington Post article on an updated international report on the rapid changes that have given a face-lift of the Arctic region. 

Malawi Fundraiser

 We are trying to raise funds for our friends in Malawi. Through money donated by the ETHS community over the last four years, some schools in Malawi have been able to purchase land and start their own farms to ensure the kids are fed throughout the school year, even during the dry season and drought periods that have led to actual famines in that part of Africa. 

The new donations are for expanding the farms to help feed not only the schools and some 1500 children, but also much of the village, which has been affected by the COVID pandemic. Even small donations of $1 and $5 add up to quite a lot, since the dollar is strong relative to local currency (malawian kwacha). 

Please consider donating. Thank you!

Ranking the Brightness of light bulbs, in basic resistor circuit

 This was a collaborative problem for the seniors. They had a network of 13 resistors, which represented identical light bulbs, and had to determine the currents through each one and rank the bulbs from brightest to dimmest. But how can you find the relative fractions of the total current in each bulb? 

This video shows how to think it through, using our usual 5 rules for resistor circuits: how to do series and parallel resistances; Ohm's law, V = IR; and Kirchhoff's two rules: In series voltages of the resistors add to the battery's voltage, and in parallel the currents in the branches add to the total current. 

We use each of these rules to figure this out. If you can understand this, then you likely have a really good conceptual understanding of resistor circuits!! 

6 Questions Physicists ask when evaluating if a claim is correct

To many, science is the process of discovery and trying to find the 'facts' of how the world works. It is supposed to be unbiased, nonpartisan, and pure. But don't ever forget that science is done and practiced by human beings, all of whom are imperfect, have biases, and make mistakes, just like everyone else. We are not 'all knowing' and have all the answers, and we never will. 

Having said this, what is the real story for how scientists go about their work? How do we know whether or not to believe a scientific claim by others? How and why should we evaluate others' work to justify their conclusions, especially when it is something important in the field or something never seen or claimed by anyone before? 

Check out this nice piece, from Symmetry magazine (this is very good if you like particle physics), which uses examples from particle physics to demonstrate how science is actually a little messy, but most importantly human - and 'facts' in science do change! Scientists are willing to change their minds over time as new results, often the result of new technologies and methods and data sets, because discovering real truth is a long, difficult process. There always is and should be debate and skepticism, but also open minds that are willing to accept new results that contradict old ones. There needs to be an open process or peer reviewed publications and presentations at conferences, so other experts can review a colleague's work openly and completely to check for mistakes or misinterpretations of the data. This is why it takes time to do science the 'right way.' 

Non-scientists sometimes are confused by this process, and the fact that 'facts' change in science. Perhaps the flipside of this is religion, where a particular doctrine or religious text states what is and is not, and that is not open for debate. Personally, I avoid using the term 'fact' in general because it implies absolute correctness - if we are talking about something in Nature, or something in human nature, these are both SO complex and dynamic, I'm not convinced we will ever find an absolute truth in anything! But that's OK, this is what makes science and life interesting, for me, at least!  

Excellent message from former NASA astronaut - how STEM skills, mindset and training relate to fixing humanity's problems

 Check out this post related to the UN Peace Week session Greek student Marios was part of. Former NASA astronaut and sister of Ms. Curry (maiden name is Metcalf) in the ETHS Math Dept, Dottie Metcalf-Lindenburger, is a former teacher and astronaut who had a mission to the International Space Station. She gives replies to the important questions of how being trained as a scientist and having that sort of mindset, values and skills, overlap those that are needed by all students who want to make a difference and help solve the big problems facing humanity. Very cool stuff! 

Mind blowing size for our Milky Way galaxy!

 If you had asked me yesterday about how wide is the diameter of our Milky Way galaxy, or most galaxies since ours is pretty 'average' and typical, I would have said something like 200,000-250,000 light-years. That has been the number astronomers have been thinking for some time. 

But new research, technology and tools have greatly changed this value. The Milky Way is now measured to be 1.9 MILLION light-years in diameter! Wow! For just one galaxy. Check it out.

Binary orbit simulator

 Thanks to a group at UCLA, here is a cool simulator if you want to get a better feel for binary orbits. You can vary masses as well as eccentricity, so make circular orbits (e = 0) or really elongated ones. Notice that in elliptical orbits, the center of mass of the system is at a focus of the two ellipses. 

Two very cool experiments at the atomic level

 We know, ever since Galileo in the 1600s, that two different masses, when dropped from the same height at the same time, and if air resistance is not a factor, the two objects land at the same time. Gravity's acceleration on objects is independent of mass. While this works well for everyday objects we can see, a big question has been does this hold true for small objects, like molecules or even atoms??? We now have the means of doing these experiments, and it turns out that yes, this is still true for atoms!! 

Check out this article from Science News about a really cool experiment! 

AND, we think we are pretty good pulling out our cell phones, and measuring time on the stop watch down to hundredths of a second. That's pretty good for everyday events we might want to time. But how small a time can humans actually measure? There are atomic clocks that are good down to nanoseconds (billionths) or even picoseconds (trillionths). A new experiment was done using x-ray photons and hydrogen molecules, though, where the wave nature of the electrons of the two hydrogen atoms were taken advantage of. 

X-ray photon were shot at H2 molecules. The photon could excite the closer electron, and then travel the tiny distance to the second hydrogen atom and excite that electron. A special type of electron microscope imaged the interference pattern caused by the two electron waves, and measured where that pattern was centered with respect to the molecule. The slight distance this point was from the midpoint of the molecule is caused by the time taken for the photon to travel the bond length of the molecule. This time was 247 zeptoseconds! A zeptosecond is a trillionth of a billionth of a second, or 10^-21 seconds!  WOW!!!!!! This is the time it takes a photon to travel the length of a hydrogen molecule! 

Read about it here!

Public Lecture at NU: A Storm of Stars, about the history of the Milky Way galaxy

 Prof. Shane Larson at NU, who is a really good guy and obviously knows his stuff, will give a free public lecture about the history of our galaxy, the Milky Way. This is at 7 pm on Wednesday, Oct. 28, online. You can register using the link. This should be really interesting, and if you enjoy astronomy and astrophysics, could be a lot of fun for you! 

STAR WARS fans - the first actual plasma retractable light saber!

 Check out this video for how The Hacksmith team created the first known retractable, colored plasma light saber, using laminar flow of gases! It is pretty cool...uh, well, it is actually incredibly hot at around 4000 degrees F!! And it cuts stuff! Thanks to my son for finding this video (he's an even bigger geek than I am, and is in school to be an actual rocket scientist). Disclaimer: DO NOT try this at home!

Room Temperature Superconductor - this is a BIG DEAL in Physics

 For decades, a dream of many physicists, chemists, engineers and material scientists has been to make a material that can be in a superconducting state at room temperature. Generally, superconductors have been a variety of materials that, when made really cold, like using liquid helium to cool down around 3 or 4 Kelvin, could lose all their electrical resistance...yes, R = 0...that is a superconductor. 

In this state, when an electrical current flows through the superconductor, there would be NO energy loss at all. You could maximize the current. At Fermilab, a superconducting solenoid would produce very strong magnetic fields on my old experiment. MRI machines are possible because of these types of superconducting magnets. 

But think about room temperature. If we could make wires and run electricity through them in a superconducting state, the nature of power production and distribution becomes totally efficient, with no heat loss in the wires. All aspects of our electronic, energy dependent world would be affected over time, in a positive way. Here is a ETHS grad's (Jaime B.) explanation of superconductivity in general: 

 

Black History Month - Black Inventors & Scientists

 Check out a listing of inventions made by Black inventors, as well as Black scientists. Let's remember how many of these women and men are also pioneers, leading the way for not only other Black people but for all women and people of color. 

Life in general is so much more interesting and pleasant when everyone has a chance to share their gifts and talents with the world, when all have a chance to share their voice and intelligence and wisdom, when cultures and interests and traditions are shared with each other, and when we recognize that in science, the concept of races doesn't really exist - there is just a human race. 

Nobel Week!!

 The Nobel Prize in Medicine and Physiology goes to 3 Americans for discovering the Hepatitis C virus, which affects millions of people worldwide. 

The Nobel Prize in Physics goes to 3 (a Brit, German, and American woman; only the 4th woman in history for a Physics Nobel!) who did pioneering work in black hole research. 

The Nobel Prize in Chemistry goes to 2 women for the first time, for developing CRISPR technology and methods. 

The Nobel Prize in Literature goes to an American poet. 

The Nobel Peace Prize goes to the World Food Programme, which consistently fed 100,000,000 people in the past year, during the pandemic.

The Nobel Prize in Economics goes to 2 Americans (both at Stanford) for auction theory.

UN Movie - Urgent Solutions for Urgent Times

 If interested, this shows a few things happening around the world that we often pay no attention to. If interested, check it out whether for the project or just because. It is 34 minutes. 

One thing to note is how often you see YOUNG PEOPLE taking the lead in so many issues!!! YOU really can help make a difference, whether on a local, national or even global level. Anything and everything helps. And keep in mind that STEM will be responsible for the ultimate solutions to pretty much all of the 17 UN SDGs. This is why we want to be aware of the issues, the broad scope of things that need to be worked on to find solutions, and that many of your interests, skills and talents will allow you to contribute, should you choose. 

One of my favorite parts is around the 13:00 minute mark - the Hole in the Wall experiment!! Check it out. 

What you can do with a Physics degree!!

 An interesting article in US News & World Report, of the broad range of jobs and opportunities one has with a physics degree. You'd be a highly trained technical problem solver of just about anything, so these are people countless groups are looking for. 

Integration & Anti-derivatives - finding areas below graphs

 We have begun to define and use derivatives in physics, for things like defining velocity and acceleration as v = dx/dt and a = dv/dt. These are equivalent to finding the slopes of tangent lines on motion graphs, and being able to find instantaneous values of different quantities. We also have our rule/short cut for finding the derivatives once we know what the function looks like. 

This works great if we are given position, x(t), in a problem. But what if we are instead given acceleration, a(t), and need to work backwards to get velocity and position as functions of time??? We have to UNDO the derivatives to get those! We need some sort of ANTI-derivative. 

It turns out that ANTI-derivatives are used to find the AREAS below graphs, and that areas are often giving us useful information about an object or system. Check out this introduction to begin learning how this all works! 

If interested in science research, see the projects that made Top 40 in the Science Talent Search!

 These are high school students with a lot of curiosity who were fascinated by some topic and question, and did the long, hard work to investigate it and find answers! Don't underestimate what teens are capable of, but unleash them and see what they can do!! 

The 2020 Top 40 Finalists in the Regeneron Science Talent Search, top prize $250,000 to one student! 

Astrophysics Seminar this Saturday - Big Star deaths and what it could mean for Earth

 An interesting topic if you like astrophysics will be this Saturday, from UIUC.

Join nuclear and particle astrophysicist, Prof. Brian Fields, for the second Saturday Physics for Everyone (SPE) lecture.
The most massive stars are the celebrities of the cosmos: they represent a small fraction of all stars, but live extravagant lives and die in spectacular and violent supernova explosions. While these events are awesome to observe, they can take a sinister shade when they occur closer to home, because an explosion within a certain "minimum safe distance" would pose a grave threat to Earthlings. We will discuss these cosmic threats to life, and show compelling evidence of a “near-miss” supernova from 3 million years ago that rained its debris upon the Earth. This amazing discovery allows us to study supernova ashes in the laboratory and confirms that nearby explosions are a fact of life in our Galaxy. We, therefore, press further, presenting recent evidence that supernova explosions could have caused biological extinctions on Earth around 360 million years ago. We conclude with tests of this hypothesis, including the search for trace amounts of radioactive supernova byproducts in fossils that witnessed the end of the Devonian period.

  Check it out and register for the webinar! 

Parents and Guardians, welcome to 3,4 Chem/Phys Physics!

 For a brief overview of the year in physics, feel free to watch this video. 

Electric potential, gradients and equipotential lines

 This video goes through the relationship between electric fields and potentials (i.e. voltage), which are the 2 fundamental quantities created at every point in space around any electric charge. These are abstract ideas, and then there is the math that goes with this relationship - the gradient. 

Check out how to think about a gradient, and how all this relates to equipotential lines and surfaces we talk about in physics. This follows from potential wells we did in mechanics. The gradient relationship is 

E = -dV/dr

So when potential varies through space, there is necessarily an electric field that exists in that space. This also helps explain why electric fields pass through equipotential lines perpendicular - there is no change in voltage along one of these lines, so there cannot be a field or even component of a field along an equipotential line. 

So check it out, there are some details and visuals that hopefully will be helpful. 

Electrostatics demos

 We would normally be doing similar things ourselves if at school; but check these out! 

Lightning video

 A pretty good overview of lightning!

Propagation of Uncertainty in labs

 In our physics classes, one experiment we do is finding speed of rolling objects. This requires us to make two different measurements, distance and time, and then calculate the speed result, v = d/t. On top of this, we normally would measure the time with a stop watch, and do multiple trials at a given distance. 

The questions becomes, knowing we are using imperfect measurements that have uncertainty, and divide them to get a result, how in the world can we combine those measurement uncertainties to get the uncertainty in the speed result??? Hmmm....

The process is called propagation of uncertainty. This video will show how to do this with a speed example, but the formula and thinking can be used in any experiment where one multiplies or divides multiple measurements! Keep in mind that if we do time trials in this example, then the uncertainty in the average time is the standard deviation of those time trials. 

How to find and use Standard Deviation in lab work

 Many believe the most important piece of a lab experiment is the result. While of course important, the most important part of experimentation is often not taught in high school - how to do an error analysis! That is, how believable and reliable are your data? If there is some huge spread in measurements with all sorts of uncertainty, then how good can results and conclusions possibly be? 

It reminds me of polling results before big elections. Suppose A is up on B in polling 51% - 49%. If this is all your given in a newscast, and it's the day before, you might cheer that A is going to win!! However, how does this conclusion change when you are informed the uncertainty of the polling is plus or minus 3%? Suddenly, we cannot reach any real conclusion about the result...it is statistically a tie, a tossup, and we'll have a nail-biter waiting for the results to come in! 

The standard way to handle uncertainty for measurements where we do multiple trials is the standard deviation. Check out how to calculate it, and how to interpret it.

Reviewing Constant Acceleration (Kinematics equations)

 Constant acceleration is the primary type of motion studied in first-year physics classes. Things like free fall with gravity (g = 9.8 m/s^2), and cars and runners starting races, or things moving down hills, can all be approximated as having constant acceleration. Keep in mind that it is a rarity to have constant acceleration in real life, but this is still a valid approximation to use. 

Check out a couple of examples to review the use of kinematics equations. This will not go away, even as we get into NON-constant forces and accelerations using the calculus. 

Using Derivatives: Redefining velocity and acceleration using motion graphs

 Calculus is one of the greatest discoveries in STEM history, and I would say in human history. Isaac Newton developed it in his studies of motion and gravity, and it is a 'tool' we will use from here on out once we get some understanding of derivatives (and later 'anti-derivatives', which will allow us to use integrals). 

Motion graphs like position vs time, velocity vs time, and acceleration vs time, are common features used to analyze motions of objects. And from last year, you may have even related velocity and acceleration to slopes of other graphs. But remember, derivative just means slope, too, only of tangent lines. 

We will now define v = dx/dt, and a = dv/dt...using slopes of tangent lines of strange curves, to determine the motion of object. This takes us to ANY MOTION, not just constant acceleration like last year!! 

Check this out to start getting some understanding. 

Introduction to Derivatives! Let's do some Calculus!

 Calculus is the mathematics of changing quantities. And one of the primary 'tools' for doing this is something called a Derivative. As usual, this is just the fancy name for a certain type of slope - the slope of a tangent line to a curve. 

It will seem weird, perhaps, to talk about slopes of curves. But this is just what we can do. And it might not seem like much at first, but the applications of this idea are vast, and we will figure some of that out over time. 

Keep in mind as you watch the video, that as far as the math goes, we are only using the normal slope equation, slope = rise/run. And then, the single step that changes a normal slope into a derivative, is a limit of two points on the curve getting unimaginably close to each other! 

But let's first define slope and see how to figure it out for a simple curve, a basic parabola. Check it out! 

The Earth's Magnetic Field weakening in certain areas, a potential reversal coming??

 The earth's magnetic field is necessary for life as we know it. It protects us from charged particles from outer space. But we know that the field has gone through dozens of reversals - there have many times when a compass needle pointed south, instead of north! Computer simulations are starting to reveal how and why this occurs, and signs of it have been observed for the past decade or two. A new 'dent' in the earth's magnetic field around one of the well known anomalies in the South Atlantic Ocean seems to fit into the continuation weakening of the field, and follows characteristics revealed and predicted in simulations leading up to reversals. 

We'll see what happens over the next couple centuries. We are actually 'overdue' for a reversal, the last one happened around 800,000 years ago. Check out a good NOVA episode on the earth's magnetic field. 

3 Chem/Phys Summer Camp

The new school year is almost upon us. And let's not hide the fact that everyone - students, teachers, parents, administrators - are some combination of nervous, scared, angry, confused, anxious, depressed, relieved, and fill in your own emotion. 

Our approach is more along the lines of developing a mindset that we are not just a class, but a learning team. We are more than classmates, we are teammates. We support each other, help each other, cheer for each other. We feel bad when another is having a bad day and try to help. We feel good when everyone 'gets it' and does well. 

This is a challenging time for everyone, so let's help each other not because some teacher wants you to...let's all actually want to help each other on our own! Let's be caring, thoughtful, compassionate and empathetic human beings who find meaning and joy in helping others through challenges. 

Class Information

You will be getting Google Classroom course numbers to sign in by the time school begins. In fact, all of your teachers will have a Google Classroom when school begins. In Physics, we will not only use Classroom, but Doc V also has the key class and unit documents housed on his school website (with Unit folders on the 3 Chem-Phys page), as well as this class blog. Check out the various pages on both the website and this blog, where there is all sorts of information not only used or class, but dozens of academic teams and extracurricular options each of you will be able to pursue if interested the next two years. 

TODAY - MONDAY, AUG. 3

We are going to break off in the Summer Camp and give you a bit of time to try a couple things asynchronously! Get used to this, because that combination of 'synchronous' Zoom class sessions and 'asynchronous' independent work will be the norm in every one of your classes. By the way, this is more like a college or adult work schedule than what you are used to in school. 

This means you have more individual control over your schedule, but also more individual responsibility for your own learning! 

To Try:

• Spend about 10 minutes to skim through the Physics website and the Physics blog. Begin to get a sense of resources, topics, activities, history, and so on. Perhaps something will already jump out at you and seem interesting! Make note of anything like this, and we can chat about it later. 

• At any time, post questions and what has been effective and not effective for you during elearning to this Google Sheet. Or you can email us separately if you don't want to share publicly. 

• Try a basic at home lab about rotational speed. You need to be logged into your eths202 account to access. We will try some of these throughout the year when we are remote. For this one, you can find any kind of sphere, any kind of disk or cylinder (like a full can of something), and if possible, a ring or hollow cylinder (like an empty can with both ends cut out). These are all objects that can roll, and you can do experiments to see if they all make it down a ramp in the same time and have the same speed at the bottom of the ramp. You did not do rotational motion last year, so this will be a new set of discoveries for you based on experimental information! 
• Our first website recommendation for the year! Check out a 3D version of the Powers of 10 video, which shows the range of smallest things to the largest! Very cool! 

Thank you for joining us today, and I cannot wait to get to know you and work with you!! 

Too cool to pass up - A photo of another solar system!

Check out this article in Science News, where astronomers have a photo of a Sun-like star with two gas giant exoplanets orbiting. Way cool!! 

Being Black in America: UIUC Chancellor Robert Jones

Dr. Robert Jones is the current Chancellor at the U. of Illinois at Urbana-Champaign, which is one of the largest public universities in the country and one of the largest and most prominent research universities in the world. He recently gave an interview about being black in America. He thinks our approach should be one we don't hear discussed a lot, which is as a public health crisis.

That would be an interesting mindset and approach to take as a nation, just as many suggest we should treat gun violence as a public health crisis...big, important issues that become politically and emotionally charged in a hurry when taking them on head-on, could be looked at in a different light, as public health, which is something that invites working together because public health is more inclusive and doesn't care what color one's skin is; just as a virus or bacterium doesn't care who its host is, the public as a whole must figure out how to handle the disease.

Women in Physics - Nadya Mason

I want to spotlight every so often, underrepresented groups in the sciences, especially fields like physics, math, computer science, and different areas of engineering, which are the big fields that still have the largest gaps in diversity - meaning lower numbers of women and people of color who take on those disciplines as majors, and who end up working in those fields. The situation is a little better since I was in graduate school in physics nearly thirty years ago, where professors were certainly predominately white and Asian men, but let's celebrate progress when we see some.

One of the rising stars in physics works at my alma mater, UIUC. Nadya Mason is an African-American woman who is a world expert in quantum mechanical nanocircuitry and is heavily involved in getting more minorities into the highest levels of STEM work, and was recently interviewed for an alum publication. She also has a TED talk outlining her work, and I recommend watching it since she talks about our gap and fear between the technologies we use everyday and our near complete ignorance of how they work.

Wholeness - the possibilities to a deeper, unforeseen part of Nature thanks to Quantum Mechanics

An American physicist, David Bohm, who Einstein once called his "spiritual son," got into science because he thought it was enough to help humanity solve its worst problems. Bohm thought poverty was the world's single biggest problem. But after years of doing science, he concluded science was not enough for the human race to find a new reality of happiness and being rid of its biggest problems. This thought, plus the bizarre reality of quantum mechanics/quantum field theory, as well as more strangeness of general relativity, led him on a quest to also determine what consciousness itself is.

These are all pieces of the human quest to figure out answers and reasons for the most fundamental questions: how and why did the universe begin, why are we here, what is the meaning of life, what is our connection to the universe...

Bohm took an approach to find out what was beyond the reaches of science, and actually came up with a scientific way of thinking about the "hidden variables" in quantum mechanics. This was perceived as a realm where we could not observe those variables, but that realm was responsible to a true interconnectedness, or wholeness, of the universe. Our consciousness is connected to the collective consciousness of humanity, which is connected to the universe as a whole. His 1952 paper on hidden variables was looked at by world experts in quantum mechanics, led by Robert Oppenheimer (the 'father of the atomic bomb' since he led the Manhattan Project during WWII), and they could not find anything incorrect about Bohm's theory...but Bohm was then sent into scientific exile from the U.S. when McCarthyism ramped up at the start of the Cold War.

It is a fascinating and intriguing story, where one must think in terms of science, philosophy, religion, and mysticism (Eastern mystics have thought about this interconnectedness and wholeness for millenia). A really well-done movie about Bohm's quest is below, with very well known physicists being interviewed, as well as the Dalai Lama.

The 'Magic number' everyone knows but no one understands!

Drum roll, please.... 1/137.

No units. A value one gets by combining the speed of light, Planck's constant, and the charge of an electron or proton. It appears in electromagnetic theory, relativity, and quantum mechanics. It is connected with all the pillars of physics, and is necessary to understand how atoms work.

But NO ONE has a clue as to why it is so important, or if it holds the key to a unified theory of physics and nature. Physicists, especially theorists, often write the number on their chalkboards, so it is always there and always on their minds.

Does this number hold the key to understanding the entire universe???? Perhaps, but we don't know. It is given the name fine structure constant in textbooks, because it was connected early on over a century ago to a particular feature of the electromagnetic spectrum (which has to do with the nature of how atoms emit light). But it is a puzzle waiting to be solved, even though all of the great physics geniuses over the past 100+ years have taken a shot at trying to figure it out.

For more, check this. For a little more technical information, check here.

A visual about the essence of 'privilege'

If you have never seen the video below, it is worth the 3-4 minutes of time. I'm posting this as we are all watching what seems to be the US imploding over the fact of systemic and institutionalized racism. We are all hearing and seeing on every social media platform and news broadcast the anger and frustration and fear that comes from another killing of a black man, George Floyd, by a police officer. And we are hearing about 'white privilege.'

This term does NOT mean automatically a white person is racist. What it does mean is that there are many aspects of our normal, everyday lives that we can go about our business without any negative consequences - but people of color often cannot do the same things we do, or have the same set of circumstances in their lives that many white people have that simply make life easier. None of us have control over what color of skin we are born into. Growing up as kids, we don't have control over the circumstances of the lives we lead. But perhaps a good and necessary first step is to recognize that the everyday 'normal' of many/most white people is not the same as the everyday 'normal' of many/most people of color. This difference in everyday normals every person must deal with goes to the essence of what white privilege means.

Obviously this is not about physics. It is much more important than physics - it is about both our individual and collective humanity, the difference between right and wrong, and about a learning and healing process our nation desperately needs so every single person can help make Martin Luther King's dream become a reality some day, when one is not judged by the color of one's skin, but instead by one's character.

The Age of AI and "Deepfakes"

We all love the realism of new graphic and video technologies, which have brought on unbelievable movies and presentation options. However, like any technology ever invented by human beings, other human beings figure out negative ways of using the tech.

Here comes the age of Artificial Intelligence and the "Deepfake." The possibility of creating totally realistic, but totally made up and fake, videos, is here. It will soon be possible to make videos of anyone doing whatever you can imagine, and posting them to set them up, and it will be near impossible to determine and prove they are fake. The implications for this are mind-boggling and terrifying. In a pretty deeply divided country presently, the deepening of the divide could happen by one fake advertisement during a campaign...and it could be done by an individual, anywhere in the world, who might not be tracked down. And endless possibilities for someone with negative intentions. Check one out - the most famous example, and remember this is really primitive since it is a year or two old.

If you are interested in computer science, this is an area we need top talent to work on to give us tools to identify fakes from reality...this is a world changer! 

Summer Opportunities for Juniors, 2020

Hi, Rising Seniors!! This has a nice ring to it!

I hope you have been well, and I miss you! But, as the shutdowns are likely to continue through the summer, and since the school will be closed, summer programs canceled, etc., there are a number of possibilities to get involved with things (remotely) over the summer, besides research options.

Check out descriptions of things for details here.

Put your name under any of these that you are interested in here.
You need to be in your eths202 account to access these.

This video does a brief description of these opportunities.

CONGRATULATIONS, Class of 2020!!

A few thoughts for you....

Rotations example: Lab problem to find moment of inertia of a rotating contraption

Thanks to Sofia for finding this sample lab-based problem. It is really similar to our bike wheel lab at school. In fact, had we been in school, we would have done this exact experiment!!

This is another example of a typical lab problem (and how we do labs in real life). What can we measure? What quantities is moment of inertia related to (think torque = I*alpha)? What graph will yield a result from its slope for the quantity we are looking for?

Check this out for a nice example with rotations.

CONGRATULATIONS CLASS OF 2020!!! Our last HAPPY FRIDAY!!!

This goes out to the seniors!! 

I love you all, and am SSSSSOOOOOOOO proud of you!!!!

Moment of Inertia with a NON-UNIFORM linear mass density....YIKES!!

Things don't usually seem promising when you hear phrases like, "non-uniform linear mass density!" That just sounds nasty difficult! But if you step back and give it a chance, it allows us to look at objects other than just, say, nice neat sticks like a meterstick, that is uniform....the mass is distributed evenly along the length of the stick, with the center of mass at the actual center of the stick. But what about something like a baseball bat, where the mass per unit length changes along the stick, as it gets wider and heavier on one side compared to the skinny side. The center of mass of a baseball bat is not at the actual middle of the bat.

Linear mass density is the ratio of Mass/Length, or M/L (the symbol is lambda). We use this ratio when we calculate the integral for the moment of inertia of a stick. But what if we want to set things up for the baseball bat? How do we find the moment of inertia for a non-uniform stick? This video shows an example, which comes from the 2018 AP exam.

SENIORS: Share your COVID-19 story!!

Seniors, PBSNewHour is using #SeniorPortrait to allow you to post and be recognized for videos about your senior year experience during the pandemic. If interested, go here to get the details and share your thoughts on Instagram, Twitter, and/or Facebook. You may get your video to be broadcast on a nightly NewsHour show, which generally has about 2 million viewers.

Lab-based problem examples for Physics classes

A classic purpose of experiments done in high school, college, and even for professional scientists, is to get experimental values for different constants or parameters used in theories or mathematical models. This is a fundamental piece of data analysis skills science students need. And very often, this process makes use of graphs that are linearized, and the slope of the graph can be used to get the value you are after.

For a class problem or lab, how do we go about using data to make a graph that will help us find some value of a constant? In physics, maybe we want to use data from some experiment to make a graph that will help us determine the mass of an object, or an acceleration value, or a spring constant value, or the value of a resistor or capacitor in some circuit.

To hopefully help you understand how to do this, this video provides 3 mechanics examples that outline the way of thinking in lab-based problems.

3 Chem/Phys Last Week AP Prep Resources

Hope all is well!! Here are some quick links for convenience:
- For practice problems similar to this year's 2 AP exam problems
- For videos on just about any topic we do (focus on anything mechanics related)
- For old AP exams, solutions (logged in with eths202)
- For other review sets and solutions, quizzam solutions, can check any unit folders (logged in with eths202)

Hope this helps!!

For this last week, try at least 5 old AP problems on any mechanics based topics you think are most beneficial for you - so think of the topics/problems that challenge you the most, and try them so we can be sure to figure out what's going on.  At least 2 of them should be lab-based. This is what will be put in HAC. Our sessions will focus on whatever topics you need to review, so we'll be doing a lot of theory and examples together - come with questions! 

The AP Mechanics exam is Monday, May 11, at 11 AM! For ALL DETAILS OF THIS YEAR'S EXAMS, SEE THIS COLLEGE BOARD RESOURCE.

College Board for Students: Getting ready for Exam Day

COLLEGE BOARD VIDEOS EXPLAINING AP EXAMS

COLLEGE BOARD EXAM DAY CHECKLIST

If interested, sign up to tutor K-8 students!

Some juniors have set up a volunteer, free tutoring service for K-8 students in District 65. If you have any interest in helping with this effort, sign up and join the fun. For more information, check out the website the students have created. This is set up in conjunction with Evanston Cradle to Career. Thank you Ana, for setting this up - it's a great day to be a Wildkit!!

Quick links for Seniors, Week of April 27

Hope all is well!! Here are some quick links for convenience:
- For practice problems similar to this year's 2 AP exam problems
- For videos on just about any topic we do (focus on anything electricity related)
- For this week's review set, can be turned in (if hand written photos can be sent/shared)
- For old AP exams, solutions (logged in with eths202)
- For other review sets and solutions, quizzam solutions, can check any unit folders (logged in with eths202)
- For last lab

From College Board, for Students: Getting ready for exam day

Hope this helps!!

For this week, try at least 5 old AP problems on any electricity based topics you think are most beneficial for you - so think of the topics/problems that challenge you the most, and try them so we can be sure to figure out what's going on.  At least 2 of them should be lab-based. This is what will be put in HAC. Our sessions will focus on currents and circuits, so we'll be doing a lot of theory and examples together. 
We also have our last high school 'lab!' It is about charging objects by induction and conduction, and you figure out a way to do a demo/simulation for the task described in the lab. A 1-minute video explaining your method, by end of Sunday. You have 2 'phone a phriend' life-lines for this! 

Seniors - 2020 AP Exam info & start of review

Here's the scoop, seniors.

All AP exams this year are 45 minutes in length, with 5 minutes needed to upload your work. For AP Physics C, both Mechanics and EM will have 2 free response problems (NO multiple choice). Go here to find more details on any AP exam you are taking. EM Exam at 1:00 PM on May 11. 

The first physics problem is 25 minutes and 60% of the score. It will almost certainly have multiple topics involved; it will be a bit more conceptual than just mathematical. While derivations are still fair game, it won't be completely math based. It is more difficult to BS one's way through conceptual questions than computational, so expect more writing than usual. Remember, they will likely want to have some calculus on the exam, and perhaps some derivation.

The second problem is 15 minutes and 40% of the score. It will be a lab-based problem. Perhaps you need to take a bunch of data and do an analysis. Or perhaps you will be given a list of available equipment and design an experiment to measure something specific. Keep in mind that a major piece of analysis is to have a mathematical model in mind, with a constant stuck in it, and you need to find the constant's value by using data - usually it involves linearizing a graph and using the slope to get the constant's value.

These exams are open book, open note! Go here to get advice about open book exams (these occur in college more frequently than in high school).

To find old AP problems that are similar to this year's problems, I will be putting the info here. You can find them in our AP Exam page on our school website. Any exam from the past decade will have lab based problems.

To me, it sounds like the AP Physics C problems this year will be more like AP Physics 1 problems. These tend to be more writing and explaining than hard-core calculations. The College Board gave as an example problem for the first problem, #3 from the 2017 Physics 1 exam. Go here to see past AP Physics 1 exams. Just focus on those problems that are on topics we study. The scoring solutions are available.

EM Topics for 2020: 
- Electrostatics: Point charges and E-fields, electric potential; F = qE, U = qV, Coulomb's law 
- E = -dV/dr, equipotentials, energy and work with charges
- Gauss & Non-Gauss
- Resistor circuits; R = pL/A (p = resistivity)
- Capacitor circuits; dielectrics
- RC circuits 

There is NO magnetism or EM induction this year!!

Review Set for the week of April 20:
- AP EM Review set I - Electrostatics to be completed by end of Friday, 4/24; solutions are on the 4 Chem/Phys page of our school site. Videos for all topics are here. 
- During our class Zoom sessions, we will take any and all questions, try some of the recommended problems together to best practice for this year. 
- Official class times: Mondays at 11 am; Wednesdays at 1:15 pm; Fridays at 10 am. 
- I've been doing 3 pm drop-ins on Tuesdays and Thursdays for juniors; will offer 2 pm drop-ins for seniors on Tuesdays and Thursdays as we get into review weeks! 
- Remember, using eths202 account you can access AP Exams and solutions. 

Worth watching - Why social distancing and masks are effective

You should really watch at least the first minute or so of this video, showing experimental and simulated studies of what we all put out when we sneeze and talk. Droplets and micro-droplets, some smaller than 1 micron. It is really interesting technology to literally see the droplets, coming from work in Japan.


Micro droplets suspending in air from MixonK on Vimeo.

Happy Friday!!!!! Stay Positive!!

Remember, if you are reading this that means you woke up and are still kicking....it is a good day!!
Happy Friday!!

AP Exam 2020 Info and Resources

Here's the scoop, juniors.

All AP exams this year are 45 minutes in length, with 5 minutes needed to upload your work. For AP Physics C, both Mechanics and E&M will have 2 free response problems (NO multiple choice). Go here to find more details on any AP exam you are taking.

The first physics problem is 25 minutes and 60% of the score. It will almost certainly have multiple topics involved; it will be a bit more conceptual than just mathematical. While derivations are still fair game, it won't be completely math based. It is more difficult to BS one's way through conceptual questions than computational. Remember, they will likely want to have some calculus on the exam, and perhaps some derivation. Air friction tends to be the trickiest for most students. Go here to see some examples/reminders of where calculus comes in. Links to relevant videos are included.

The second problem is 15 minutes and 40% of the score. It will be a lab-based problem. Perhaps you need to take a bunch of data and do an analysis. Or perhaps you will be given a list of available equipment and design an experiment to measure something specific. Keep in mind that a major piece of analysis is to have a mathematical model in mind, with a constant stuck in it, and you need to find the constant's value by using data - usually it involves linearizing a graph and using the slope to get the constant's value.

These exams are open book, open note! Go here to get advice about open book exams (these occur in college more frequently than in high school).

To find old AP problems that are similar to this year's problems, I will be putting the info here. You can find them in our AP Exam page on our school website. Any exam from the past decade will have lab based problems.

To me, it sounds like the AP Physics C problems this year will be more like AP Physics 1 problems. These tend to be more writing and explaining than hard-core calculations. The College Board gave as an example problem for the first problem, #3 from the 2017 Physics 1 exam. Go here to see past AP Physics 1 exams. Just focus on those problems that are on topics we study. The scoring solutions are available.

Mechanics Topics: 
- Kinematics and 1-D, 2-D motion
- Newton's laws and circular motion
- Energy and work
- Momentum and impulse
- Rotations and angular momentum

There is NO simple harmonic motion or Gravity/orbital motion/flux this year!!

3 Chem/Phys - Welcome back from Break!!! Finishing up

With hope you all had a fun, restful and healthy spring break, welcome back!!

What's new? What's been fun for you? What time have you been waking up the past week?

As we have at the very least a few more weeks of remote learning, 3 BIG reminders:
1. be checking in with attendance each day with the school; your teachers have no choice but to go by the official list we receive, regardless of whether we see you on Zoom or get emails from you on a given day
2. remember that counselors, social workers, and psychologists are all available if you need anything personally, for college, or any other school matters. 
3. there is the sharing Google Sheet, to give ideas of things to try

AP Details for Mechanics: 
- will be at 11:00 AM on May 11
- 2 problems: the first you will have 25 minutes to read and write your responses (60%), similar to #3 on this AP 1 exam; and a second one you will have 15 minutes (40%).
- you can use a calculator
- just free response, NO multiple choice
- a lot of conceptual understanding will be tested, some calculations/derivations possible. The second one will be to design and analyze a lab experiment on some topic.
- No simple harmonic motion/oscillations, gravity and orbital motions
- Once you submit the first problem you will not be able to go back to it.
- Go Here to get details of any AP exam for this year

Completing the Course:
To hopefully have something a little different and physical, try to do a few of the options in this at-home mini-lab for rotations. Depending what you have available at home, try at least 3 of the options in the lab by the end of Friday, April 17. These are just some fairly simple things to do. For instance, if you happen to have any hard boiled eggs, there is one quick option for those and raw eggs.

Even though it will not be on the AP exam, today just a brief introduction into simple harmonic motion (SHM). The standout example of SHM is something oscillating on a spring. The gist of this will be using F = ma = -kx to give us our one case of a second order differential equation (a is the 2nd derivative of position). Of course, this is different from things we've already done, such as with basic motion or air friction, which have all been first order differential equations that we can do an integral (antiderivative) to solve.

For our 2nd order DE, the solutions for functions of time will be sines and cosines. Hopefully this makes sense, if you want to describe a periodic motion mathematically, we should probably use periodic functions, and those happen to be the solutions to what Newton's 2nd law gives us for a spring.

Relevant Videos: 
Because we won't do all of SHM like we normally would, relevant videos are linked here for those who are interested. For those who have an interest in learning all of SHM, I can do some other examples on Tuesday's 3 pm Zoom session.
- simple harmonic motion, the basics
- SHM more details: initial conditions and phase angle
- simple pendulum and small-angle approximation
- more advanced: SHM for a stick oscillating due to a spring (rotating, oscillating stick)
- a 1-D example of the Schrodinger equation to see where quantum numbers (integers) come from!

Lab: PhET Simulated Experiment for SHM: if you want to vary parameters and see the effects on the oscillations.

There is a simple harmonic motion packet in our SHM folder of the 3 Chem/Phys school web site. There are some recommended practice problems for those who want to try any. These will not be 'assigned' since we won't need them for the AP exam. We will do a couple together as examples, so you can see what all this is about.

AP Review Materials: 
Review sets are all available on the 3 Chem/Phys site. There are three sets to get the basic ideas back for the material that is fair game for this year's AP exam:
AP Review Set I 
AP Review Set II
AP Review Set III 
Each has solutions files available, and we had some of these for the review for the 1st semester final.
All of my videos are here.

And then the AP Exam page. You need to be logged in to your eths202 account to access.

The College Board has online review sessions for all AP courses.

Iron rain....really, I'm serious!!

Nature never ceases to amaze, as humans look around more and more, there are ever more surprises. This one caught my eye - astronomers have found a planet called Wasp-76b, some 390 light years away (which is really close!). It is a "hot Jupiter" planet, meaning it is big, nearly twice as big as Jupiter, in an orbit really close to its star. The sunny side is over 4000 C, which is hot enough to melt and vaporize iron. Any iron in the atmosphere, such as iron dust, melts and actually can become an iron vapor! Now, as the planet rotates, on the dark side of the planet, it is cool enough for that iron vapor to condense and form droplets heavy enough to fall...this planet should have iron rain!! I don't know if anyone has ever come up with this idea in any science fiction, but now it looks like the strangeness and creativity of nature never lets up!

If someone is looking for something to do over spring break and our isolation, change the lyrics of "Purple Rain" (by Prince), and make a new song, "Iron Rain."  😉

ETHS Friday song, dedicated to the Senior Class of 2020!!

Enjoy, seniors!!

Former Chem/Phys student doing European modeling for COVID-19

A former Chem/Phys student, Seth Flaxman (Class of 2004), is lead author from Imperial College on predictions of COVID-19 in the coming weeks in 11 European countries. Check out their report, and see what a technical, scientific paper on this type of problem looks like. He made the code available, which is on GitHub, as well, if you want to see what this looks like for a complex system to model. Within the next week, most of the growth charts should start to turn over and begin the flattening of the curve...hopefully Europe is moving past the inflection point. I have not found a similar, up to date report for the US yet.

Thanks, Seth!! Seth did some really cool CABS research on periodic heat flow while at ETHS, and actually went to London to represent the US through the JSHS contest (which he won at Loyola, and then at nationals to advance as one of six US students to the International fair). He built the experiment in his bedroom, and also modeled the heat flow using FlexPDE.

3 Chem/Phys: Juniors, How Have You Been????

HAPPY MONDAY,  everyone!!

First things first - how is everyone? How are your families? 

You know how I put an emphasis on not only your physical health, but social, emotional and mental healths, as well. We are entering week 3 of isolation, distance learning, and being away from each other, your friends, classmates (i.e. learning team members), and everything else at school. Small changes can be difficult, but this has been a BIG change in our lives and routines.

If you are feeling lonely, anxious by the 24/7 news coverage and chatter about COVID-19, bored, depressed, stressed, or anything else, know that this is normal under these circumstances. And also know that we all have many resources to turn to if we need help, or just someone to talk to: counselors, social workers and psychologists are all available through the school. 

Housekeeping items

• Keep checking in with the school each day this week
• While these three weeks have been 'Act of God' days with the state, and no grades have been given to anything you've done in classes, hopefully you have been trying the work to still best learn the content as best you can. STARTING TUESDAY, we have been told that we are back to more normal school, and will begin to issue formal grades for 4th quarter. In the coming weeks we will find out details about semester exams and quarter/semester grades. Official attendance also begins Tuesday - this will be done solely through an email link you will receive daily, and that is all teachers are allowed to use. We CANNOT mark you present if you do not check in with the school, even if we see you on a Zoom session!!  
• AP Exams will be given in May. They will be 45 minutes, free response, and on material up to March in your AP classes. We do not yet know the logistics - should get this April 3.
• Try to keep up as best you can, and we all know this is a challenge because we are mostly on our own. Keep group chats going, call each other, do your own Zoom/Skype/other study groups, make use of video and other online resources, make use of your textbook, email me any time with questions/concerns/deep thoughts/the meaning of life/etc...
• We have a Google Sheet set up for us to share suggested things to try while in our quarantine. New games, videos, links, recipes, whatever! Also, a separate sheet is set up for anyone to ask questions about material, and anyone can help out with responses. This may be useful if you should be trying or thinking about something outside of a class session. 
• If you ever are bored or curious or motivated to try any sort of project, don't forget to chat with me and there are all sorts of things you could try! Refer to the past email I sent, or check out an activities options page on the blog.

3 Chem/Phys

Hope your last unit of Chemistry went well! We will pick up with rotational motion, and complete it with angular momentum the next few days. 

Here's the meeting schedule given to us from the administration, as of today: 

We will offer a couple Zoom sessions each week, at 11 am Monday and 1:15 pm Wednesday. The links to the sessions will be emailed to the group each day. We are NOT allowed to video class sessions. We do have the individual topic videos on the blog, with nearly all topics we covered throughout the year. You can watch the videos before and/or after live class sessions. There will be one official 45-minute office hour for Science classes, at 10 am Friday. These are the only official times we have to meet as a class. I check emails constantly throughout the day and will be available just about any time, every day, if you have questions. 

The other main online resource is our class site on the school web page. Our unit folders are there, the past quizzam solutions, review sets, and so on can be found for anything we've done this year. Check out the solutions to the last rotations quizzam. On the 3 Chem/Phys page, there are already review sets for the AP exam, and the solutions. There is the AP Exam page, with problems going back to the 1970s, and all the solutions in its own folder. 

Unit Packet

Angular Momentum Packet

Relevant videos for Angular Momentum

- If you need to review the rotations basics: our chart of linear vs rotational

- Introduction and examples of the 2 ways to find and use angular momentum

- Conservation of angular momentum examples

- Conservation of angular momentum for ballistic pendulum 

- Conservation of BOTH linear and angular momentum (hit a pencil on a table, and get both types of motion)
- This is the Mechanical Universe video on Angular Momentum I showed on Zoom; start around the 13:20 mark

- Supplemental: Case where there is a non-constant torque, and non-constant angular acceleration
- Supplemental: Using Kepler's and Newton's laws to navigate in space - going to other planets
- a PowerPoint on Angular Momentum found by Sofia...might be useful for some!

Practice Problems
Try to have the Ch 10 problems for Wednesday's 1:15 pm class session, so we can take questions and check setups. 

- Ch. 10 #37,39,41,42,95  on page 3 of packet

Try to have the 2005 and 1998 AP problems by Friday morning's office hours at 10 am, so we can take questions and check setups.

- We will use most of the AP problems as examples during our sessions; recommended to try some of these old APs on your own or with a virtual group. These are:

        Practice Problems on page 6

        AP from 2005 on page 8

        AP from 1998 on page 9

And Seniors....that's a wrap!!!

Happy Friday!!!! This should sound familiar, maybe not look familiar??!?! 😄

Today we finish off your high school physics career, as far as content goes!

CONGRATULATIONS ON YOUR SURVIVAL SKILLS ever since sophomore year!! 

Have a few seconds of celebration!!

Today we will wrap things up by defining one of the great mathematical achievements in science, which are known as Maxwell's equations. Maxwell was a wizard of math and had deep physics knowledge and intuition, and he was about the only one of his era that saw the connections between a bunch of individual, scattered discoveries over about one hundred years worth of work. Everyone knew that there was some connection between electricity and magnetism, but no one else really understood how to make the deep connections or to put things into a single theory or set of equations. This is what Maxwell figured out, and to this day the four equations are all that are needed to understand everything about electricity, magnetism, and electromagnetism.

We will use portions of a video to see what the equations are, and how they ultimately led Maxwell to predict electromagnetic waves and the speed of light, long before this was confirmed in the lab...just by using some MV calculus.

The other thing we will try are breakout rooms in Zoom. We will have a chance to meet up with others in the session and talk through a few questions about EM induction.

I know trying to do EM induction, which is one of the trickier topics in physics, through distance learning is not easy. But know HOW PROUD OF YOU I am, for your efforts, the way you've adapted, and how you've remained (hopefully) pretty positive despite the circumstances!! You are amazing, wonderful young women and men, and be sure to stay that way forever!! Go ahead and CELEBRATE a bit!

e-Learning for 4 ChPh: Last Topic!!

Happy Tuesday, one and all!! I hope you are well, and good health for you and your families! A good way to start each day is to think of something you appreciate; or think of something nice you have done for someone else the past day or two; or think about something nice someone did for you! Remember counselors, social workers and school psychologists and nurses remain available for anyone.

Some housekeeping items:

• be sure to vote for senior awards
• please keep checking in daily with the school on the Google Form
• the school is supposed to get more logistics answers for AP Exams by April 3, but for us plan on material covered being through electricity: electrostatics with point charges, equipotentials, Gauss, non-Gauss, resistor circuits, capacitors (w/ dielectrics), RC circuits; sounds like all free response so you have to show work, password protected files for the exam, 45 minutes long, I suspect a lot of Honor System built in to this. You can start review any time, and a good initial guide is our EM Objectives. There are all sorts of review sets in the 4 Chem/Phys folder. You can start looking over old material in any of your AP classes any time. Colleges should still be sticking to their policies about giving credit, placement, etc., according to the College Board. 
• please email me with updates on any practice problems you have been trying. Because almost all of them are old AP problems, you can be self-checking/grading to see how you are doing, but please let me know and any questions you may have. You can also pose questions to the learning team, as well as share fun things to try while quarantined. 

EM Induction is your last physics topic! We have one last item within induction, and that is an application in circuits: what happens when we put inductors, which are essentially little solenoids, into circuits with resistors, and finally when we combine inductors with capacitors? We will even throw in a blurb about transformers, and end with Maxwell's equations - and how did Maxwell predict light is an EM wave, and he even predicted the speed of light, decades before this was proven experimentally, just from math?!?!

Your last bit of physics is in Packet #4. The relevant videos for all this are: 

- Maxwell's displacement current: how capacitors really work, and how a changing E-field behaves just like a current

- Inductors in series with resistors (RL circuit)

- Inductors in parallel with resistors

- Last circuit: LC Circuits, the heart and soul of wireless technology!

- Supplemental: The basics of inductors from an engineer's point of view

- Supplemental: How does a transformer work

- Maxwell's equations and EM waves: everything in E&M comes together!

Practice problems are in Packet #4. This includes a lab using a PhET simulation - I hope it works on your ChromeBook! There are some good explanations, examples, diagrams in your textbook for all the induction topics.