The absolute refractive indices of glass and water are 3/2 and 4/3 respectively. If the speed of light in glass is 2×108m/s, then the speed of light in water will be ____×108.

The absolute refractive indices of glass and water are

3 / 2

and

4 / 3

respectively. If the speed of light in glass is

2 \times 10^{8} m / s

, then the speed of light in water will be

2.25 \times 10^{8} m / s

.
Given,
Refractive index of glass

n_{g} = \frac{3}{2}

n_{g} = \frac{Speed of light in vacuum}{Speed of light in glass}

\Rightarrow \frac{3}{2} = \frac{Speed of light in vacuum}{2 \times 10^{8}}

Speed of light in vacuum = \frac{3 \times 2 \times 10^{8}}{2}

= 3 \times 10^{8} m / s

Now, Refractive index of water

n_{w} = \frac{4}{3}

n_{g} = \frac{Speed of light in vacuum}{Speed of light in glass}

\Rightarrow \frac{4}{3} = \frac{3 \times 10^{8}}{Speed of light in glass}

Speed of light in water = 2.25 \times 10^{8} m / s

The absolute refractive indices of glass and water are $3 / 2$ and $4 / 3$ respectively. If the speed of light in glass is $2 \times 10^{8} m / s$ , then the speed of light in water will be ____ $\times 10^{8}$ .