Glass has refractive index $\frac{3}{2}$ and water has refractive index $\frac{4}{3} .$ If the speed of light in glass is $2 \times 10^{8} \mathrm{~m} / \mathrm{s}$, then the speed of light in water will beA. $1.6 \times 10^{8} \mathrm{~m} / \mathrm{s}$B. $2.25 \times 10^{8} \mathrm{~m} / \mathrm{s}$C. $1.8 \times 10^{8} \mathrm{~m} / \mathrm{s}$D. $2 \times 10^{8} \mathrm{~m} / \mathrm{s}$

Home » Glass has refractive index and water has refractive index If the speed of light in glass is , then the speed of light in water will beA. B. C. D.

Glass has refractive index $\frac{3}{2}$ and water has refractive index $\frac{4}{3} .$ If the speed of light in glass is $2 \times 10^{8} \mathrm{~m} / \mathrm{s}$ , then the speed of light in water will be
A. $1.6 \times 10^{8} \mathrm{~m} / \mathrm{s}$
B. $2.25 \times 10^{8} \mathrm{~m} / \mathrm{s}$
C. $1.8 \times 10^{8} \mathrm{~m} / \mathrm{s}$
D. $2 \times 10^{8} \mathrm{~m} / \mathrm{s}$

Physics

Glass has refractive index $\frac{3}{2}$ and water has refractive index $\frac{4}{3} .$ If the speed of light in glass is $2 \times 10^{8} \mathrm{~m} / \mathrm{s}$ , then the speed of light in water will be
A. $1.6 \times 10^{8} \mathrm{~m} / \mathrm{s}$
B. $2.25 \times 10^{8} \mathrm{~m} / \mathrm{s}$
C. $1.8 \times 10^{8} \mathrm{~m} / \mathrm{s}$
D. $2 \times 10^{8} \mathrm{~m} / \mathrm{s}$

Correct answer is B.

$\begin{array}{l} \quad \mathrm{v}_{\text {water }}=\frac{\mathrm{c}}{\mathrm{n}_{\text {water }}} \\ \therefore \quad \mathrm{v}_{\mathrm{water}}=\frac{3 \times 10^{8}}{(4 / 3)}=2.25 \times 10^{8} \mathrm{~m} / \mathrm{s} \end{array}$

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