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A disc is placed on the surface of pond ...

A disc is placed on the surface of pond filled with liquid of refractive index `(5)/(3)`. A source of light is placed 4m below the surface of liquid. Calculate the minimum area of the disc so that light does not come out of liquid.

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To solve the problem, we need to determine the minimum area of the disc that will prevent light from escaping the liquid. This involves calculating the critical angle for total internal reflection and the radius of the circular area from which light can escape. ### Step-by-Step Solution: 1. **Identify the Given Data:** - Depth of the light source below the surface of the liquid, \( d = 4 \, \text{m} \) - Refractive index of the liquid, \( \mu = \frac{5}{3} \) ...
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