How does diffraction relate to the behavior of light as a wave?

Hint: Diffraction is defined as a change in the direction of the sound wave or the light wave which is caused by the presence of an obstacle in the path.

Complete step by step answer:
Diffraction is mainly caused by the one wave of the light being shifted by a diffracting object and this will cause the wave to have interference with itself. Also, this interference can be either constructive or destructive. However, the intensity of the wave will increase when the interference is constructive.

Also, the diffraction refers to the fact that the radiation invades an area behind the obstacle which can be seen through this effect through the Huygens principle. The Huygens principle states that every point on the front of the wave becomes the source of the secondary spherical waves. Thus whenever the front meets an obstacle, one of the secondary spherical waves can bend behind the edge of the obstacle thereby giving the diffraction effect in the next front.

Light also reflects, refracts and, diffracts in the same manner as waves. It would also undergo the same interference as that of the waves and also it would exhibit a Doppler effect just as waves.

Whenever the light moves from one medium to another medium it will change the directions which are called refraction and it will be a wave-like behavior. Thus the light behaves like waves.

Note:
1. The diffraction increases with the increase in wavelength.
2. Wave interference is defined as the interaction of the waves with other waves.