Question

Explain the quantum concept of light.

Answer 1

Concept of quantization of energy: Max Planck proposed the quantum concept in 1900 in order to explain the thermal radiations emitted by a black body and the shape of its radiation curves. According to Planck, the matter is composed of a large number of oscillating particles (atoms) which vibrate with different frequencies. Each atomic oscillator which vibrates with its characteristic frequency emits or absorbs electromagnetic radiation of the same frequency. It also says that

1. If an oscillator vibrates with frequency v, its energy can have only certain discrete values, given by the equation.

E_n = nhv n = 1, 2, 3 ………..

where h is a constant, called Planck’s constant.

2. The oscillators emit or absorb energy in small packets or quanta and the energy of each quantum is E = hv.

This implies that the energy of the oscillator is quantized that is, energy is not continuous as believed in the wave picture. This is called the quantization of energy.