A 27 mW laser beam has a cross-sectional area of 10 mm². The magnitude of the maximum electric field in this electromagnetic wave is given by :
[Given permittivity of space $$ \in $$₀ = 9 $$ \times $$ 10^–12 SI units, Speed of light c = 3 $$ \times $$ 10⁸ m/s]

The magnitude of torque on a particle of mass 1 kg is 2.5 Nm about the origin. If the force acting on it is 1 N, and the distance of the particle from the origin is 5m, the angle between the force and the position vector is (in radians) :

A paramagnetic substance in the form of a cube with sides 1 cm has a magnetic dipole moment of 20 $$ \times $$ 10^–6 J/ T when a magnetic intensity of 60 $$ \times $$ 10³ A/m is applied. Its magnetic susceptibility is

In a hydrogen like atom, when an electron jumps from the M-shell to the L-shell, the wavelength of emitted radiation is $$\lambda $$. If an electron jumps from N-shell to the L-shell, the wavelength of emitted radiation will be: