An electron is accelerated by a potential difference of $12000\, volts$. It then enters a uniform magnetic field of ${10^{ - 3}}\,T$ applied perpendicular to the path of electron. Find the radius of path. Given mass of electron $ = 9 \times {10^{ - 31}}\,kg$ and charge on electron $ = 1.6 \times {10^{ - 19}}\,C$

In case Hall effect for a strip having charge $Q$ and area of cross-section $A$, the Lorentz force is

An electron is moving along the positive $x$-axis. If the uniform magnetic field is applied parallel to the negative $z$-axis. then

$A.$ The electron will experience magnetic force along positive $y$-axis

$B.$ The electron will experience magnetic force along negative $y$-axis

$C.$ The electron will not experience any force in magnetic field

$D.$ The electron will continue to move along the positive $x$-axis

$E.$ The electron will move along circular path in magnetic field

Choose the correct answer from the options given below:

Two very long, straight, parallel wires carry steady currents $I$ and $-I$ respectively. The distance  etween the wires is $d$. At a certain instant of time, a point charge $q$ is at a point equidistant from the two wires, in the plane of the wires. Its instantaneous velocity $v$ is perpendicular to the plane of wires. The magnitude of the force due to the magnetic field acting on the charge at this instant is

When a charged particle moving with velocity $\vec V$ is subjected to a magnetic field of induction $\vec B$ , the force on it is non-zero. This implies the

Which particles will have minimum frequency of revolution when projected with the same velocity perpendicular to a magnetic field