Two coherent waves have individual intensities in the ratio 9:4. What is the visibility of the resulting interference fringes?
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Two coherent waves have individual intensities in the ratio 9:4. What is the visibility of the resulting interference fringes?

G1 Physics · Accepted Answer

Take the intensities as 9I and 4I. Then, I(max) = 25I, I(min) = I. Visibility is V = [I(max)−I(min)] ÷ [I(max)+I(min)] = (25−1) ÷ (25+1) = 24 ÷ 26 = 12 ÷ 13. Correct option: B.