A point source is 12 cm below a water-air surface. Take μ of water=4/3. What is the radius of the circular region through which light can emerge?
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A point source is 12 cm below a water-air surface. Take μ of water=4/3. What is the radius of the circular region through which light can emerge?

G1 Physics · Accepted Answer

sin C=3/4, cos C=√7/4 and tan C=3/√7. Thus r=12×3/√7=36/√7 cm.