The Standard Model is the name of the theory we use to help us understand what makes up the universe (i.e. particles of matter) and how matter interacts (fundamental forces of nature). It breaks down the hundreds of particles in nature down to 6 quarks, 6 leptons, and a few force carrying bosons, along with the Higgs boson that provides mass to particles in the first place. Check out a summary video!
Tuesday, September 12, 2017
Big Bang - Start of our Universe
What is the Big Bang theory for the creation of the universe? In principle it is as easy as saying there was a large explosion of unimaginably hot energy, which 'cooled' to form the fundamental particles and forces that we see in the universe today. This happened about 13.7 billion years ago, according to present-day best measurements and calculations.
As with any scientific theory, no one should put any belief into it until there are predictions made from the theory that are then tested experimentally and through physical observations. Over the past 100 years, the theories of Einstein and the eventual Big Bang models have gone through this slow process, and confirmation of the key ideas have occurred, making this the best understanding we have for the universe's creation.
Check out this video that explains the gist of the Big Bang theory, and a couple reasons why scientists believe it is a valid theory. Check here for a quick example of the Doppler effect.
As with any scientific theory, no one should put any belief into it until there are predictions made from the theory that are then tested experimentally and through physical observations. Over the past 100 years, the theories of Einstein and the eventual Big Bang models have gone through this slow process, and confirmation of the key ideas have occurred, making this the best understanding we have for the universe's creation.
Check out this video that explains the gist of the Big Bang theory, and a couple reasons why scientists believe it is a valid theory. Check here for a quick example of the Doppler effect.
Wednesday, September 6, 2017
Projectile Review
As we get back into motion, projectiles are a classic case of 2-D motion from sophomore year. Let's bring it back! Check out one video that focuses on the basic properties and concepts of projectiles, a video with a couple examples of how to set up these problems (and they are all pretty much the same!), and if interested, one that goes into the reason why projectiles move on a parabolic path, as well as the effect of air friction on that parabola.
Check these out as needed as you bring back the problem solving skills with the homework set of problems.
Check these out as needed as you bring back the problem solving skills with the homework set of problems.
Tuesday, August 29, 2017
Fact or Fake?!?! Try to tell which articles are which!
If you are alive an breathing, you should know there is a battle going on, especially in the political world, over factual or fictitious news, reality versus alternative facts. Check out a site, Factitious, that provides real articles, but some of which are from legitimate, reputable news organizations (meaning stories are verified, vetted by journalists), and others are from well-known tabloids (usually made-up or embellished stories). You may be surprised by many of these! I was duped on several! :-(
Sunday, August 27, 2017
Why include UN Sustainable Development Goals in classes? How can we not?!
The United Nation's Sustainable Development Goals, or SDGs, include 17 aspects of global life that can be and NEED to be addressed in the next decade. These goals are related to everything from global education to climate change to ending hunger to gender equality to clean water and air. The motto is "17 Goals to Transform Our World."
Another reason to take action on these NOW, rather than later, is because the techniques/methods/knowledge that will be developed to achieve these goals by 2030 are necessary to have in place as the population continues to grow, where we expect to have an additional 2 billion people on the planet by around 2050.
Let's be aware of these, see which goals our studies are related to, and make even a small difference where we can! It is our world, so let's fix it and take care of it together!@TeachSDGs
Another reason to take action on these NOW, rather than later, is because the techniques/methods/knowledge that will be developed to achieve these goals by 2030 are necessary to have in place as the population continues to grow, where we expect to have an additional 2 billion people on the planet by around 2050.
Let's be aware of these, see which goals our studies are related to, and make even a small difference where we can! It is our world, so let's fix it and take care of it together!
Friday, August 18, 2017
Why are Astronauts "weightless" in the space station?
This is easily one of the biggest MISCONCEPTIONS there is in science!!! A good majority of people would guess because there is no gravity in space....NNNNNOOOOOOO!!!!!
THERE IS LOTS OF GRAVITY ACTING ON THE SPACECRAFT!!! WHAT DO YOU THINK KEEPS IT IN ORBIT??????
So if there is a lot of gravity acting on the astronauts from the earth, how can they float???
It is actually because all satellites are constantly FREE FALLING towards the earth, because of gravity. And if you are on a scale in an elevator that is free falling, guess what the scale would read....0!! You would be 'apparently weightless' because everything falls with the same acceleration when gravity is involved. You would not be truly weightless, since there is still gravity acting on you.
Check out this really good video from the Veritasium channel.
THERE IS LOTS OF GRAVITY ACTING ON THE SPACECRAFT!!! WHAT DO YOU THINK KEEPS IT IN ORBIT??????
So if there is a lot of gravity acting on the astronauts from the earth, how can they float???
It is actually because all satellites are constantly FREE FALLING towards the earth, because of gravity. And if you are on a scale in an elevator that is free falling, guess what the scale would read....0!! You would be 'apparently weightless' because everything falls with the same acceleration when gravity is involved. You would not be truly weightless, since there is still gravity acting on you.
Check out this really good video from the Veritasium channel.
How do Satellites Work? The very basics...
Satellites are cool and help make modern life possible, but they are also confusing to many people - how can these things stay in orbit for decades without crashing into the earth?
The key ideas come from projectile motion. Gravity creates acceleration downward, but we need to give a fast enough speed perpendicular to gravity so the satellite moves in a curve. If you play with that speed, what you'll find is that there is a special speed where, as it falls, it moves very far forward. The trick is to have the curve of the satellite match the curve of the earth - thankfully the earth is more or less round!! This special speed is called the orbital velocity.
Check out the video, and I hope it helps!
The key ideas come from projectile motion. Gravity creates acceleration downward, but we need to give a fast enough speed perpendicular to gravity so the satellite moves in a curve. If you play with that speed, what you'll find is that there is a special speed where, as it falls, it moves very far forward. The trick is to have the curve of the satellite match the curve of the earth - thankfully the earth is more or less round!! This special speed is called the orbital velocity.
Check out the video, and I hope it helps!
Understanding some Properties of Projectiles
Forget the math for a few minutes - focus on some of the important concepts and interesting properties of projectiles, at least under ideal conditions (i.e. no air friction!). This gets into the importance of independent horizontal and vertical motions that are really the key to understanding projectile motion, and multi-dimensional motion in general. To understand why parabolic paths form, check out this video. To check out some basic math for projectile problems, check out this video.
Check it out, and hopefully this will make some sense to help you understand what the math is telling us when we do problems.
Check it out, and hopefully this will make some sense to help you understand what the math is telling us when we do problems.
Thursday, August 17, 2017
Projectile trajectories - With and Without Air Friction
All of us are familiar with the arch-shaped path, or trajectory, a ball follows when we throw it. When symmetric, this is a parabola, and is the common shape we use in physics classes for projectiles. But WHY is it an arch of any kind, let alone a parabola? And why are we lying to you about projectiles???
We ignore air friction when we do projectile problems, but in life this makes it more complicated, and also no longer a perfect parabola. Check out this video to get a sense of why parabolas form when there is no air friction, and what the trajectory looks like in a more realistic environment, with air friction.
We ignore air friction when we do projectile problems, but in life this makes it more complicated, and also no longer a perfect parabola. Check out this video to get a sense of why parabolas form when there is no air friction, and what the trajectory looks like in a more realistic environment, with air friction.
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