Which of the following can travel at the speed of light in a vacuum?
A) light, radio waves, X-rays, and gamma rays
B) Only light-all other electromagnetic waves travel slower than the speed of light.
C) light, atoms, X-rays, and subatomic particles (e.g., electrons)
D) light, infrared radiation, ultraviolet radiation, and subatomic particles (e.g., electrons)

Question

Quizplus · Accepted Answer

All electromagnetic waves, including light, radio waves, X-rays, and gamma rays, travel at the speed of light in a vacuum.

Which of the Following Can Travel at the Speed of Light