Question

The dispersive power of a prism depends upon:

• A. Shape of prism
• B. Material of prism
• C. Height of prism
• D. Angle of prism

Answer 1

The correct option is B

Material of prism

Reason for the correct option-

1. Dispersive power is defined as the difference in refraction between the longest wavelength and the shortest wavelength that enters a prism.
2. Refraction depends on the refractive index of the prism.
3. Which in turn depends on the material of the prism.
4. Hence, the dispersive power depends on the material of the prism.

Reason for the wrong option

1. All the other factors are the same for both the wavelengths and won't change the difference between refraction.
2. The angle of the prism, the height of the prism, and the shape of the prism do not affect the refraction of different wavelengths differently.

Hence, option B is correct.