An electron and a proton having the same momenta enter perpendicularly into a magnetic field. What are their trajectories in the field?

A solenoid 2 m long and 4 cm in diameter has 4 layers of windings of 1000 turns each and carries a current of 5 A. What is the magnetic field at its centre along the axis? [$$\mu_0=4\pi\times10^{-7}$$ Wb/Am]

A particle of charge 'q' and mass 'm' moves in a circular orbit of radius 'r' with angular speed '$$\omega$$'. The ratio of the magnitude of its magnetic moment to that of its angular momentum depends on

A current carrying loop is placed in a uniform magnetic field. The torque acting on the loop does not depend upon