- Measure the position of the red ball at the beginning and a latter time. Use this information to calculate the initial position and velocity of of the red ball.
- Write the equation of motion for the red ball in the box below. Your equation will look something like:

Then click on the button to make the blue ball follow your equation of motion. If the two balls do not move together, check you calculations of initial position and velocity of the red ball.*x*+*v**t

Exercise created by Scott Bonham, Western Kentucky University.

Physlet by Wolfgang Christian, Davidson College