Which of these follows from the theory of relativity?
A) Mass is relative to one's frame of reference.
B) Time is relative to one's frame of reference.
C) Length is relative to one's frame of reference.
D) Mass, time, and length are all relative to one's frame of reference.
E) None of these things are relative to one's frame of reference.

Question

Quizplus · Accepted Answer

The theory of relativity states that all three (mass, time, and length) are relative to one's frame of reference. This is known as the principle of relativity. This idea is what led to the famous equation E=mc², which relates energy, mass, and the speed of light.

Which of These Follows from the Theory of Relativity