Question

In the phenomena of diffraction of light, when blue light is used in the experiment in spite of red light, then

• A. fringes will become narrower
• B. fringes will become broader
• C. no change in fringe width
• D. None of these

Answer 1

The correct option is A fringes will become narrower

Fringe width is directly proportional to wavelength of light used.

Wavelength of blue is less than the wavelength of red light, therefore fringes will become narrower.