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.