NOTE: the answer for #28 is C, not D.

Gravitation Practice Problems KEY

Here is the Crash Course Video on Circular Motion:

Here’s a nifty site from NASA which tracks most of the satellites in orbit around the Earth. Amazing!

And here is an animation showing the sped up history of space junk.

Remember how we always treat inertial mass, and gravitational mass the same? That is, we assume the mass of an object due to its inertia, is equivalent to its mass due to gravity. This is called the equivalence theorem, and folks like Galileo, Newton, and Einstein believed it to be true. But what if it isn’t? Check out this article about research that is testing this theorem. So cool!

Circular Motion & Gravitation Ultimate Review Problems and Key

Physicist risks life to prove circular motion formula:

And here is the planning of the above stunt:

Try out this Circular Motion Simulation from PhET (The University of Colorado’s Physics Simulator site

Click on the image below to play. Go to the site and play around with placing the ladybug and the beetle on the turn-table and give them a spin. Check out the “Rotation Tab” to see graphs of the motion. So nerdy. So awesome!