Question

What happens to the pattern when you:

A. Increase the wavelength? (What happens for double slit pattern and single slit pattern?)

B. Slits are moved closer (what happens for double-slit patterm?)

C. Each slit is widened (what happens to single-slit pattern?)

Answer 1

A. We know the wavelength of light is directly proportional to the fringe width so if the wavelength of the light is increased then the width also increased.

B. If the Slits are moved closer in the double slit experiment then the fringe width will decrease, If we further decreased the slit width then the diffraction patterns will not occurs.

C. We know the conditions of the Single slit pattern, the slit width is must greater or comparable to the wavelength of light used. The same phenomena will occur when the slit width is increased at the constant wavelength and the wavelength is increased at constant slit width. If the slit width is increased at a constant wavelength the fringe width will also be increased.

I am attaching the relevant images