If we are traveling at 0.9 times the speed of light and we turn on a flashlight pointed toward the front of the spaceship, how fast is the light moving from the flashlight?
A) 0.9 times the speed of light
B) 1.9 times the speed of light
C) the speed of light
D) 0.1 times the speed of light
E) No one really knows what will happen under these circumstances.

Question

Quizplus · Accepted Answer

The speed of light is constant, regardless of the speed of the observer or the source. Therefore, from the perspective of someone inside the spaceship or someone outside observing the spaceship, the light will still be moving at the speed of light. This is one of the fundamental principles of Einstein's theory of relativity.

If We Are Traveling at 0