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Question
In Young' s experiment the ratio of intensity at the maxima and minima . in the interference pattern is 36 : 16. What is the ratio of the widths of the two slits?
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Solution
`I_(max)/I_(min)=((A_1/A_2+1)/(A_1/A_2-1))^2`
`Let A_1/A_2=r`
`therefore I_(max)/I_(min)=((r+1)/(r-1))^2`
`therefore 36/16=((r+1)/(r-1))^2`
`therefore 6/4=((r+1)/(r-1))`
`therefore r=5/1`
`A_1/A_2=5/1`
Ratio of width `=(A_1/A_2)^2=25/1`
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