Question

If red light is replaced by white light then width of diffraction pattern will

Answer 1

The fringe width is inversely proportional to the wavelength of light for a diffraction pattern. Now the wavelength of red light is grater than the white light since the wavelength of white light is the combination of the 7 colours.Hence the fringe width will be decreases for red light.

Answer 2

Answer:

The fringe width and interference will decrease if if the red light it is replaced by the blue light from the source. This is because blue light wavelength is lower and its intensity is is low when compared to red light. As the wavelength of the light is directly proportional to the fringe width of the wave.