Question

The speed of light is about 3.00 × 105 km/s. It takes approximately 1.28 seconds for light reflected from the

moon to reach Earth. What is the average distance from Earth to the moon?

Answer 1

Distance = (speed) x (time)

Distance = (about 3 x 10⁵ km/s) x (approximately 1.28 sec) =

approximately about 3.84 x 10⁵ km.

The actual average distance between centers is 384,400 km. Pretty close !