Four particles-proton, electron, alpha, and neutron-enter a region of constant magnetic field with same velocities. The magnetic field is perpendicular to the velocity .
A] Which particle [s] are not be deflected by the magnetic field ?
B] Which particle [s] are deflected by the magnetic field ?
C] Which particle experiences maximum force ? Justify .

Explanation

A] Only neutron is not deflected by the magnetic field . Magnetic force is given by F = q v B. For a neutron, charge q = 0 and hence, F = 0
B] Proton, electron, and alpha particles are deflected as they carry a charge.
C] Alpha particle experiences maximum force because it has the maximum charge.