Chapter 32, Problem 1FTD

A prism bends blue light more than red. Is the same true of a diffraction grating?

To determine

Whether a diffraction grating bends blue light more than red.

Answer to Problem 1FTD

In diffraction grating red lights bend more than blue light.

Explanation of Solution

The prism works because of refraction while diffraction grating works on the principle of diffraction. In refraction lower wavelength bends more than higher wavelength lights.

This is the reason why prism bends blue light more than red. However, in diffraction higher wavelengths bend more than lower wavelengths. Thus in diffraction grating red lights bends more than blue light.

Conclusion:

In diffraction grating red lights bend more than blue light.