Question

What is effect on fresnel biprism experiment, when the white light is used ?

• A. Fringe are effected
• B. Diffraction pattern is spreaded more
• C. Central fringes are white and all others are coloured
• D. None of these

Answer 1

Answer: (C)

Central fringes are white and all others are coloured

Fresnel biprism is a setup to replicate young's double slit experiment using prism. So the same behaviour is seen here too.

When light is white. center will receive all wavelengths and appear white. Rest will have absence of some wavelengths due to interference and will appear coloured.

Answer. C) Central fringes are white and all other are coloured