electromagnetic energy to kinetic energy

Hi Dear friends,
I have a homework and I can not figure out how to do that. I'm so stressed. May you can help.
I have a moving charged particle placed in electrostatic field of E0 and magnetostatic field of B0. There is no radiation from a large volume surrounded the charge. Now I need to find from conservation law of electormagnetic energy as :
∫J.E dv
the kinetic energy of this particle:

E=1/2 mv^2

I don't have any idea!
May help me with that.
Tnx

you forgot to mention what u need to find. please mention that and be specific :)
if u need to find the velocity or other such parameter, the equation would be 0.5m(v^2)=QV here V=voltage Q is charge (i.e W=QV ,ke is replaced by workdone due to any electromangetic field) maybe this is what u need.

Hello Dear Usama,
My exact meaning was that i need to prove:

int(J.E dv)=1/2(mv^2)
I don't know how to prove this

http://en.wikipedia.org/wiki/Kinetic_energy it explains what u need i suppose.