A charged particle of specific charge qm=α is released from origin at time t=0 with velocity V¯=V0i^+j^ in uniform magnetic field  B¯=B0i^. Co-ordinates of the particle at time t=πB0α  are.

α=qm, Path of the particle will be a helix of time period T=2πmBoq=2πB0α  The given time  t=πB0α=T2∴ Coordinates of particle at time  t=T2Would be  VxT/2,0,−2rHere,  r=mV0B0q=v0B0α ∴The coordinates are VoπB0α,0,−2V0Boα .