Question

what is the meaning of zero rest mass

Answer 1

Zero rest mass means when the particle is at rest, it's mass is zero. For example, photon has zero rest mass, means practically it has no mass. But, since photon is not at rest, it has finite energy hv.

Answer 2

ans = Zero rest mass means when the particle is at rest, it's mass is zero. For example, photon has zero rest mass,means practically it has no mass. But, since photon is not at rest, it has finite energy hv.
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