Question

Which of the following statements on red colour light is true?

• A. It has low refractive index and suffers high deviation
• B. It has low refractive index and suffers low deviation
• C. It has high refractive index and suffers high deviation
• D. It has high refractive index and suffers low deviation

Answer 1

The Correct Option is B

To determine which statement about red light is true, we need to consider the concepts of refractive index and light deviation.

1. Refractive Index: The refractive index of a material indicates how much it slows down light compared to a vacuum. A lower refractive index means the light travels faster through the material, while a higher refractive index indicates the light travels slower.

2. Deviation: In optics, deviation refers to the change in direction of a light ray when it passes through a medium with a different refractive index. The amount of deviation depends on the refractive index; lower refractive index results in lesser deviation and vice versa.

For red light:

• Red light has a longer wavelength compared to other colors in the visible spectrum. This usually results in a lower refractive index when it passes through most media like glass or water.
• Because of its lower refractive index, red light undergoes less deviation than other colors like violet or blue, which have higher refractive indices and experience greater bending.

Based on this understanding, the correct statement is: It has low refractive index and suffers low deviation.

Answer 2

Red light has the longest wavelength among visible light, which means it has the lowest frequency.

Because of its longer wavelength, it has a lower refractive index in optical media. As a result, when light passes through a prism or lens, red light is least deviated compared to other colors.

So, red light has:

• Low refractive index
• Low deviation

Final Answer: It has low refractive index and suffers low deviation