An $e^-$ is moving parallel to a long current carrying wire as shown. Force on electron is
$0.4 \times {10^{ - 18}}\,N$
$0.8 \times {10^{ - 18}}\,N$
$0.8 \times {10^{ - 16}}\,N$
$1.6 \times {10^{ - 18}}\,N$
A charge $Q$ moves parallel to a very long straight wire carrying a current $l$ as shown. The force on the charge is
A charge having $q/m$ equal to $10^8\, C/kg$ and with velocity $3 \times 10^5\, m/s$ enters into a uniform magnetic field $0.3\, tesla$ at an angle $30^o$ with direction of field. The radius of curvature will be ......$cm$
Two charged particles traverse identical helical paths in a completely opposite sense in a uniform magnetic field $B$ = $B_0\hat{k}$
A uniform magnetic field $B$ and a uniform electric field $E$ act in a common region. An electron is entering this region of space. The correct arrangement for it to escape undeviated is
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............ $m{s^{ - 1}}$