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

An electron moves with speed $2 \times {10^5}\,m/s$ along the positive $x$-direction in the presence of a magnetic induction $B = \hat i + 4\hat j - 3\hat k$ (in $Tesla$) The magnitude of the force experienced by the electron in Newton's is (charge on the electron =$1.6 \times {10^{ - 19}}C)$

If cathode rays are projected at right angles to a magnetic field, their trajectory is

A proton (mass $m$ and charge $+e$) and an $\alpha - $particle (mass $4m$ and charge $+2e$) are projected with the same kinetic energy at right angles to the uniform magnetic field. Which one of the following statements will be true

An electron has mass $9 \times {10^{ - 31}}\,kg$ and charge $1.6 \times {10^{ - 19}}C$ is moving with a velocity of ${10^6}\,m/s$, enters a region where magnetic field exists. If it describes a circle of radius $0.10\, m$, the intensity of magnetic field must be

A charged particle moving in a magnetic field experiences a resultant force