If an observer sees an object moving past them at 90% of the speed of light, what will its length appear to be?
A) The object will look longer than if it were at rest.
B) The object will look shorter than if it were at rest.
C) The object will look shorter than if it were at rest while it is coming toward them and longer after it has passed them.
D) The length of the object will appear to be unchanged from when it is at rest since it is a solid object.

Question

Quizplus · Accepted Answer

According to the theory of relativity, objects moving at a significant fraction of the speed of light will appear contracted in the direction of motion to a stationary observer. This phenomenon is known as length contraction.

If an Observer Sees an Object Moving Past Them at 90