Question

definition of relative in physics

Answer 1

It refers to the theory of Einstein that is space and time are not absolute or you can say that the speed of light in a vacuum is constant and independent of the source or observer. Or if you are having problem in understanding this term then u can simply change the relative to with respect too

Answer 2

Relative in physics --

Relative simply means any reference frame that  is moving at constant velocity with respect to the earth.  or we can say WITH RESPECT TO any constant object. It is also used in einstein equaion of time and space  but we this theory in higher studies.

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