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]

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:

A monochromatic light is incident at a certain angle on an equilateral triangular prism and suffers minimum deviation. If the refractive index of the material of the prism is $$\sqrt 3 $$, then the angle of incidence is:

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