Question

A diffraction is obtained by using a beam of red light. What will happen if the red light is replaced by the blue light

[KCET 2000; BHU 2001]

• A. Bands will be narrower
• B. Bands become broader and further apart
• C. No change will take place
• D. Bands disappear

Answer 1

The correct option is A

Bands will be narrower

Band width µl,

Ql_blue < l_red, hence for blue light the diffraction bands becomes narrower and crowded together.