What happens to the fringe pattern if in the path of one of the slits a glass plate which absorbs 50% energy is interposed?

Options

A. The bright fringes become bright and dark fringes become darker
B. No fringes are observed
C. The fringe width decreases
D. None of the above

Answer

D

Explanation

In normal Young's double slit apparatus,
`I_(1)=I_(2)=I_(0)`
`I_(max)=(sqrt(I_(1))+sqrt(I_(2)))^(2)=4I_(0)`
and `I_(min)=(sqrt(I_(1))-sqrt(I_(2)))^(2)=0`
When one of the slit is covered by a glass plate
`I_(1) lt I_(0),I_(2)=I_(0)`
`I_(max) lt 4I_(0) and I_(min) gt0`