An $\alpha -$ particle of $1\,MeV$ energy moves on circular path in uniform magnetic field. Then kinetic energy of proton in same magnetic field for circular path of double radius is......$MeV$

Two charges of same magnitude move in two circles of radii $R_1=R$ and $R_2=2 R$ in a region of constant uniform magnetic field $B _0$. The work $W_1$ and $W_2$ done by the magnetic field in the two cases respectively, are such that

An electron (mass = $9.0 × $${10^{ - 31}}$ $kg$ and charge =$1.6 \times {10^{ - 19}}$ $coulomb$) is moving in a circular orbit in a magnetic field of $1.0 \times {10^{ - 4}}\,weber/{m^2}.$ Its period of revolution is

This question has Statement $1$ and Statement $2$ . Of the four choices given after the Statements, choose the one that best describes the two Statements.

Statement $1$: A charged particle is moving at right angle to a static magnetic field . During the motion the kinetic energy of the charge remains unchanged.

Statement $2$: Static magnetic field exert force on a moving charge in the direction perpendicular to the magnetic field.

A electron $(q = 1.6 \times 10^{-19}\, C)$ is moving at right angle to the uniform magnetic field $3.534 \times 10^{-5}\, T$. The time taken by the electron to complete a circular orbit is......$µs$

If $\alpha $ and $\beta  - $ particles are moving with equal velocity perpendicular to the flux density $B$, then the radii of their paths will be