Question

The packets of light energy are called
(A) Electrons
(B) Neutrons
(C) Photons
(D) Positrons

Answer 1

Hint: Light energy is a kind of kinetic energy with the ability to make types of light visible to human eyes. Light is defined as a form of electromagnetic radiation emitted by hot objects which can be perceived by us. These radiations may or may not be visible to the human eye. Light energy propagates in the form of waves.

Complete step by step answer:
Continuing the discussion of light energy, the energy imparted by the light waves or the electromagnetic waves is absorbed in the form of particles. The energy of light waves is transferred in the form of energy packets, called photons. The photon is a type of elementary particle that comprises waves of electromagnetic radiation. Maxwell showed that photons are just electric fields travelling through space. Photons have no charge, no rest mass, and travel at the speed of light.
Photon is interesting; it is considered to be its antiparticle and since its rest mass is zero, it is not considered as matter. The energy and the momentum being carried by the photons depends on the frequency of the electromagnetic radiation.
From the above discussion, we can say that the packets of light energy are called photons. Hence option (C) is the correct option.

Note: If we did not have the elementary knowledge about photons, we could look at the other options and still make the correct choice. Let’s see how. Neutrons and electrons are atomic particles. Since light is a form of a wave, it is not constituted of atoms and as such, neutrons and electrons cannot be our answer. Positrons are the antiparticles of electrons and are formed during the decay of nuclides. Thus neutrons, electrons and positrons are all atomic particles and unrelated to light energy. That leaves only photons, so it must be our answer.