An electron with energy 0.1 keV moves at right angle to the earth's magnetic field of 1 $$\times$$ 10$$-$$4 Wbm$$-$$2. The frequency of revolution of the electron will be
(Take mass of electron = 9.0 $$\times$$ 10$$-$$31 kg)
Two charged particles, having same kinetic energy, are allowed to pass through a uniform magnetic field perpendicular to the direction of motion. If the ratio of radii of their circular paths is $$6: 5$$ and their respective masses ratio is $$9: 4$$. Then, the ratio of their charges will be :
The magnetic moment of an electron (e) revolving in an orbit around nucleus with an orbital angular momentum is given by :
A coil of n number of turns wound tightly in the form of a spiral with inner and outer radii r1 and r2 respectively. When a current of strength I is passed through the coil, the magnetic field at its centre will be :