Question

The dual nature of radiation is shown by

• A. Photoelectric effect alone
• B. Diffraction and reflection
• C. Photoelectric effect and diffraction
• D. Refraction and diffraction

Answer 1

The correct option is C

Photoelectric effect and diffraction

The explanation for the correct option:

In the case of option C,

Photoelectric effect:

This is the phenomenon of the ejection of electrons from a metal surface when the light of sufficiently high frequency falls upon it.

Diffraction:

1. It is the phenomenon of bending light around the sharp corners and spreading it into the regions of the geometrical shadow. The light waves are diffracted only when the size of the obstacle is comparable to the wavelength of the light.
2. If the size of the slit or the obstacle is made small. then the light enters the geometrically prohibited regions, showing thereby that the light bends around the corners of the slit or the obstacle.

Dual nature of radiation:

Particle nature - This is shown by the photoelectric effect.

Wave nature - This is shown by the diffraction of light.

The explanation for the incorrect options:

Reflection:

When the light traveling in a medium strikes a reflecting surface, it goes back into the same medium obeying certain laws.

Refraction:

It is the phenomenon of change in the path of light as it goes from one medium to another. The cause of the refraction of light is that light travels at different speeds in different refracting media.

So option (C) is correct.