Posted by edward on .
according to einstein's mass energy relation
M= m'/root[1(v^2/c^2)]
Where M is mass of particle when it moves with velocity 'v'
And m' is its initial mass.
When particle moves with velocity of light i.e. When 'v=c' then
M= m'/0 =infinity i.e. Infinite mass
But a photon of light can have velocity of light.
So does this possess infinite mass?!!

physics £££ 
Damon,
no, it has zero rest mass m' so its mass is undefined at any speed.
As you know of course it does have finite energy and momentum. 
physics £££ 
Damon,
see Wikipedia:
" .... In empty space, the photon moves at c (the speed of light) and its energy and momentum are related by E = pc, where p is the magnitude of the momentum vector p. This derives from the following relativistic relation, with m = 0:[15]
E^{2}=p^{2} c^{2} + m^{2} c^{4}.
The energy and momentum of a photon depend only on its frequency (ν) or inversely, its wavelength (λ):
E=\hbar\omega=h\nu=\frac{hc}{\lambda}
\boldsymbol{p}=\hbar\boldsymbol{k},
where k is the wave vector (where the wave number k = k = 2π/λ), ω = 2πν is the angular frequency, and ħ = h/2π is the reduced Planck constant.[16]
Since p points in the direction of the photon's propagation, the magnitude of the momentum is
p=\hbar k=\frac{h\nu}{c}=\frac{h}{\lambda}. ......"