Length Contraction Using all of the equations, try to derive the following answer - L = L, v1 - L = Is the shortening of distance between two points (points A and B) in units that is comparable to L L= Proper Length as measured by an observer at rest in units that is comparable to L v= velocity of the moving object in m/s or relative to the speed of light c = speed of light at 2.997x108 m/s approx. 3.0 x 10 # m/5