What do you mean by electron emission? Explain briefly various methods of electron emission.

Briefly discuss the observations of Hertz, Hallwachs and Lenard.

Explain the effect of potential difference on photoelectric current.

Explain how frequency of incident light varies with stopping potential.

Explain why photoelectric effect cannot be explained on the basis of wave nature of light.

Give the quantum concept of energy proposed by Max Planck.

Obtain Einstein’s photoelectric equation with necessary explanation.

Explain experimentally observed facts of photoelectric effect with the help of Einstein’s explanation.

Give the construction and working of photo emissive cell.

Derive an expression for de Broglie wavelength of electrons.

Briefly explain the principle and working of electron microscope.

Describe briefly Davisson – Germer experiment which demonstrated the wave nature of electrons.