when a body travels with the speed of light its mass increase or decreases. i know the Einstien equation tell me the answer and its perfect explanation..................

m = m_o/(1-v²/c²)^1/2

m_o is rest mass of particle , v is speed of particle ...

when particle moves at high velocity whose magnitude is near speed of light ....

at this condition denominator will decrease & so mass will increase ...

ITS MASS INCREASES A TIME WILL CAME AT WHICH REAL MASS = APPARENT MASS THIS CAN BE DECIDED BY THE FORMULA        M=M./(1-V2/C2)1/2

As velocity increases mass increases and at the velocity of speed mass becomes infinity and body explodes into pieces