A mass spectrometer is a device which select particle of equal mass. An iron with electric charge $q > 0$ and mass $m$ starts at rest from a source $S$ and is accelerated through a potential difference $V$. It passes $\rho$ through a hole into a region of constant magnetic field $\vec B\,$ perpendicular to the plane of the paper as shown in the figure. The particle is deflected by the magnetic field and emerges through the bottom hole at a distance $d$ from the top hole. The mass of the particle is 

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

An electron is allowed to move with constant velocity along the axis of current carrying straight solenoid.

$A.$ The electron will experience magnetic force along the axis of the solenoid.

$B.$ The electron will not experience magnetic force.

$C.$ The electron will continue to move along the axis of the solenoid.

$D.$ The electron will be accelerated along the axis of the solenoid.

$E.$ The electron will follow parabolic path-inside the solenoid.

Choose the correct answer from the options given below:

A particle of charge per unit mass $\alpha$ is released from origin with a velocity $\bar{v}=v_0 \vec{i}$ in a uniform magnetic field $\bar{B}=-B_0 \hat{k}$. If the particle passes through $(0, y, 0)$ then $y$ is equal to

In toroid magnetic field on axis will be the radius $=0.5\, cm ,$ current $=1.5\, A ,$ turns $=250,$ permeability $=700$ (in Tesla)