A particle of specific charge α starts moving from the origin under the action of an electric field →E=E0^i and magnetic field →B=B0^k. Its velocity at (x0,y0,0) is (4^i+3^j). The value of x0 is
252αE0
From work-energy theorem, ΔWE+ΔWB=ΔK
⇒qE0x0+0=12mv2=12m(32+42)
⇒qmE0x0=252
⇒αE0x0=252
∴x0=252αE0