Question

Does light have mass ? Also give reason for ur ans.

Answer 1

http://answers.yahoo.com/question/index?qid=20090819111028AAzeLWC

Answer 2

yes, but it is in the form of energy. From Einstins mass energy equivalence principle energy and mass are not two different intity and you know that a wave l carry energy and momentum.

Answer 3

Einstien's energy momentum relation is
\[E ^{2}=p ^{2}c ^{2}+(mc ^{2})^{2}\]
when particle is at rest then p=0 but the photons are not found in rest as they are high speed particles so they don't have rest mass, i.e. then their momentum is zero so the above relation becomes,
\[E ^{2}+(mc ^{2})^{2}\]
taking root on both sides,
\[E=mc ^{2}\]
therefore it has relativistic mass and light bends toward gravity.