momentum principle

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Physics Tips for Media

You probably already know how I feel about the “media” and their physics explanations (see attacks). Let me summarize the problem. There are a whole bunch of cool shows on tv that deal with sciency stuff – that is good. These shows then try to teach some science along with their demos and explosions and…

Hat tip to Frank for sending me a link to this video: If you have never done a demo like this (without the motorcycle), you should. It really isn’t too difficult. Here is a video of my version: Inertial demo from Rhett Allain on Vimeo. So, the question is: is the motorcycle thing real or…

Faster than terminal velocity

I had so much fun creating graphs for the Red Bull Stratos Space Jump calculation, that I figured I should make some more. Can you fall faster than terminal velocity? That is the question. Air Resistance Air resistance is a force exerted on an object as it moves through some stuff – air in this…

Stratos Space Jump

Red Bull is sponsoring this sky dive from really really really high up – Stratos: Mission to the Edge of Space. Seems dangerous. The basic idea is that Felix Baumgartner will take a balloon ride up to 120,000 feet and jump out. Here are some questions: Will he reach supersonic speeds? The Red Bull site…

Apolo Ohno Physics

It is winter Olympics time and time for physics. The event that I always gets me thinking about physics is short track speed skating. It is quite interesting to see these skaters turn and lean at such high angles. All it needs is a little sprinkling of physics for flavor. Check out this image of…

R2 flying at a constant speed

Since my previous post on R2-D2 flying was so popular, I thought I would follow it up. I was going to add these two points in the comments, but a separate post seems to make more sense. Point 1 – R2 flies at a constant speed Well, he obviously doesn’t always have to fly at…

Flying R2-D2, you are doing it wrong

You know I can’t help but like Star Wars. Even with the new stuff, I watch it. Recently, I was watching the Clone Wars cartoon and noticed something odd about the way R2-D2 flies. I know what you are saying….”the odd thing is that he flies at all. Why didn’t he fly in episodes 4-6?”…

In a MythBusters episode some time ago, Adam and Jamie jumped off a building. There was some cool stuff in this, but I want to focus on the acceleration data they collected. Before jumping into a pit of foam, they first wanted to test the set up by dropping a dummy into it and measuring…

It’s odd that I have talked about these forces so much. First, I talked about how centrifugal forces were not real and the difference between centrifugal and centripetal forces. Then I talked about how sometimes, fake forces are good. Finally, I talked about the origin of the words centrifugal and centripetal. (note: “talked about” means…

RP 6: Throwing a fooball, Part II

In part I of this post, I talked about the basics of projectile motion with no air resistance. Also in that post, I showed that (without air resistance) the angle to throw a ball for maximum range is 45 degrees. When throwing a football, there is some air resistance this means that 45 degree is…