Optics Question 1154

Question: What is the effect on Fresnel’s biprism experiment when the use of white light is made

[RPMT 1998]

Options:

A) Fringe are affected

B) Diffraction pattern is spread more

C) Central fringe is white and all are coloured

D) None of these

Show Answer

Answer:

Correct Answer: C

Solution:

With white light, the rays reaching the centre has zero path difference. So we get white fringe at the centre and coloured near the central fringe.