An electron falling freely under the influence of gravity enters a uniform magnetic field directed towards the south. The electron is initially deflected towards:

An electron is moving in a circular path under the influence of a transverse magnetic field of $3.57 \times 10^{-2} \, T$. If the value of $e/m$ is $1.76 \times 10^{11} \, C/kg$,the frequency of revolution of the electron is

Assertion $(A)$: When a proton and a neutron enter into a transverse magnetic field with equal speeds,they trace circular paths of equal radii.
Reason $(R)$: In a transverse magnetic field,the period of revolution of a charged particle in a circular path is directly proportional to the mass of the particle.

An $\alpha$-particle of mass $m$ moves on a circular path of radius $r$ in a plane inside and normal to a uniform magnetic field $B$. The time taken by this particle to complete one revolution is . . . . . . .

The motion of a moving electron is not affected by:

$A$ charged particle moves through a magnetic field perpendicular to its direction. Then