Suppose, A is moving with constant speed c/2 and B is stationary. A fires a beam in direction of his travel. A measures the speed of light as c. B also measures the speed of light as c obviously. But when we ask B to claim what is speed measured by A, then what should be B's answer?(adsbygoogle = window.adsbygoogle || []).push({});

I guess the B's answer is according to STR:

= (c - c/2)/(1 - (c*c/2)/(c^2))

= c

If I am right in above then how can B claim that A measure speed of light as c?

Summary:

A measures c.

B measures c.

But how can B claim that A measures c?

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# Speed of Light

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