The fringe widthh in a biprism experiment is 0.3 mm. what will be the fringe width, if the whole experiment setup is immersed in water of refractive `(4)/(3)?a^(n)w=(4)/(3)`

Options

A. 0.4 mm
B. 0.225 mm
C. 0.5 mm
D. 0.15 mm

Answer

B

Explanation

In water `lamda` will decrease, `lamda'=(lamda)/(n)`
`X'=(lamda'D)/(d) and X=(lamdaD)/(d)`
`therefore (X')/(X)=(lamda')/(lamda)=(lamda)/(nlamda)=(1)/(n)`
`therefore X'=(X)/(n)=(0.3)/(4//3)=(3xx0.3)/(4)`
`therefore X'=0.225 `mm.