Question

Which of the following is true about the speed of light?

A.It depends on the wavelength
B. In a vacuum, it is a constant value that does not depend on the observer.
C.It is slowest in a vacuum unless an observer is moving towards the source.
D.In a vacuum, it varies depending on the color of the light.

Answer 1

B. In a vacuum, it is a constant value that does not depend on the observer.