The refractive indices of glass and water with respect to air are 3/2 and 4/3 respectively. If speed of light in glass is 2×108 m/s, find the speed of light in water.
CBSE OUTSIDE DELHI - SET 3 2016
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$\text{Refractive index of a medium} = \frac{\text{Speed of light in air}}{\text{Speed of light in the medium}}$$\frac{3}{2} = \frac{\text{Speed of light in air}}{\frac{2 \times 10^{8} \text{m/s}}{\text{Speed of light in air = 3} {\times 10^{8} \text{m/s}}}}$
$\text{Speed of light in water} = \frac{3 \times 10^{8} \text{m/s}}{4/3} 2.25 \times 10^{8} \text{m/s}$
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