In the above demonstration you will see the coordinate frame of a stationary observer (rest frame). Another observer is moving at a constant velocity of 0.9c. Assume that both reference frames use the same units for time and distance. Upon choosing a formula, a red ball will appear at the origin of the rest frame and the columns of the table will fill with data. The ball moves with constant velocity in both frames. u and u' are the velocities of this ball in each reference frame. Remember that c = 1.
Section 2 Exercises: