Header and Image Map

The Basics of Relativity

Lesson 1: Relativity - What is it?

  1. Fermilab's Time Dilation Challenge.
  2. The Basics of Relativity (6 seconds)
  3. The Relativity Game - Challenge what you know!

Note: For Fermilab's Time Dilation Challenge and The Relativity Game, you need Shockwave. You may painlessly Download Shockwave here if you do not have it.

Lesson 2: Time Dilation

  1. The equation.
  2. Where does that come from?
  3. I still don't get it! Give me the basketball analogy.
  4. So what? There's an equation. How do I use the equation in the game?
  5. Practice Problems.
  6. Examples to aid your practice.

Lesson 3 : Relativistic Mass

  1. The equation.
  2. Where does that come from?
  3. I still don't get it! Give me the space pool analogy.
  4. So what? There's an equation. How do I use the equation in the game?
  5. Practice Problems.
  6. Examples to aid your practice.

Lesson 4 : Length Contraction

  1. The equation.
  2. Where does that come from?
  3. I still don't get it! Give me the pole and the barn analogy.
  4. So what? There's an equation. How do I use the equation in the game?
  5. Practice Problems.
  6. Examples to aid your practice.

Einstein's First Postulate of Special Relativity

The first postulate is most easily understood by comparing measurements you make in a stationary reference frame to measurements you make for the identical situation while you are in an airplane traveling at a constant velocity of 300 miles per hour.

Question:

If you were stationary, you would drop a ball and it would drop straight down. What about on the airplane traveling 300 miles per hour. What would happen to the dropped ball?

Question:

If you were stationary and you pushed a 0.15 kg baseball forward with a force of 62.8 Newtons over a distance of 2.0 meters:
  1. What acceleration would the ball experience?
  2. What initial velocity would the ball have with respect to you?
  3. What final velocity would the ball have with respect to you?

Question:

If you were in a plane traveling at 300 miles per hour and pushed a 0.15 kg baseball forward with a force of 62.8 Newtons over a distance of 2.0 meters:
  1. What acceleration would the ball experience?
  2. What initial velocity would the ball have with respect to you?
  3. What final velocity would the ball have with respect to you?

If you were on a part of the trip where it was completely smooth, and your velocity stayted constant at 300 miles per hour, there is no lab you could do that would verify your movement. Scientists believe that every experiment they perform "at rest" on the earth would be the same if performed on the smooth airplane ride.

The laws of physics are the same in all reference frames moving with constant velocities!

 


© Brian Wegley, 1998
Comments and suggestions can be sent by e-mail to
Brian Wegley of Glenbrook South High School..
This page last updated on 7/23/98.