An electron having kinetic energy $T$ is moving in a circular orbit of radius $R$ perpendicular to a uniform magnetic induction $\vec B$ . If kinetic energy is doubled and magnetic induction tripled, the radius will become
$\frac{{3\,R}}{2}$
$\sqrt {\frac{3}{2}} \,R$
$\sqrt {\frac{2}{9}} \,R$
$\sqrt {\frac{4}{3}} \,R$
Proton with kinetic energy of $1\;MeV$ moves from south to north. It gets an acceleration of $10^{12}\; \mathrm{m} / \mathrm{s}^{2}$ by an applied magnetic field (west to east). The value of magnetic field :.......$mT$ (Rest mass of proton is $1.6 \times 10^{-27} \;\mathrm{kg}$ )
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 beam of electrons is moving with constant velocity in a region having electric and magnetic fields of strength $20\;V{m^{ - 1}}$ and $0.5 T$ at right angles to the direction of motion of the electrons. What is the velocity of the electrons............ $m{s^{ - 1}}$
A particle is moving in a uniform magnetic field, then
A charged particle is moving in a uniform magnetic field in a circular path. Radius of circular path is $R$. When energy of particle is doubled, then new radius will be