Question

Diffraction of light was discovered by
A. Young
B. Hertz
C. Grimaldi
D. Malus

Answer 1

We have to know what diffraction of light is. So diffraction of light happens when a light wave passes through a slit which is approximately the size of, or even smaller than that light’s wavelength. It has various phenomena which happens when a wave hits an obstacle or a slit.

Complete answer:
Diffraction of light is the bending of the light around a corner and which causes shadows. There are two types of diffraction. One is single slit diffraction, the other one is double slit diffraction. In this single slit diffraction we need a coherent light source which interferes with itself and makes a distinctive pattern which is called diffraction pattern. The path difference by the top two rays are $\Delta L = \dfrac{a}{2}\sin \theta$.

Now what is double slit experiment or double slit diffraction. So here we use two such coherent sources like a single slit experiment. From this experiment we get to know about the wave theory of light. All these two diffraction experiments are invented by the scientist Young. That is why these experiments are called Young’s single slit experiment and Young’s double slit experiment. In this double slit experiment Young used one coherent source and let the passed through two more slits which made that one coherent source two. But here the right answer will be Grimaldi. So the right option would be option c. he was an Italian scientist.

Hence, option A is correct.

Note: We can get confused by the option a and option c. because Young did maximum experiments about diffraction. Like single slit and double slit. So the maximum student will give the option a. as the right answer. But that is not the truth.