A neutron, proton, an electron an `alpha`-particle enter a region of constant magnetic field with equal velocities. The magnetic field is along the inward normal to the plane of the paper. The tracks of the particles are labeled in figure. The electron follows track......... and the alpha-particle follows track.

Answer

d,b

Explanation

Z Path C is undeviated. Therefore, it is of neutron’s path. Form Fleming’s left hand rule magnetic force on positive charge will be leftwards and on negative charge is rightwards. Therefore, track D is of electron. Among A and B one is of proton and other of `alpha`-particle.
Furtehr `r=(mv)/(Bq)` or `r prop m/q:.gamma_(alpha)gtgamma_(p)`
Or track B is of `alpha` -particle