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Consider the situation of the previous p...

Consider the situation of the previous problem, if the mirror reflects only 64% of the light energy falling on it, what will be the ratio of the maximum to the minimum intensity in the interference pattern observed on the screen ?

A

4:1

B

9:1

C

16:1

D

81:1

Text Solution

Verified by Experts

The correct Answer is:
A
Given that the miror reflects 64% of energy (intensity) of light
So, `I_1/I_2=0.64=16/25`
`=r_1/r_2=4/5`
So, `I_(max)/I_(min)=((r_1+r_2)^2)/((r_1-r_2)^2)`
`=((4+5)^2)/(4-5)^2)=81:1`
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