Question

If the speed of light in air is 3 $\times$ ${10}^8$ m/s and speed of light in water is reduced by a factor of 1.3 when compared with that of the speed of light in air. Find out the speed of light in water?

• A. $2.25\times$​​ ${10}^{8}m{s}^{-1}$
• B. $3\times$​​ ${10}^{8}m{s}^{-1}$
• C. $330m{s}^{-1}$
• D. $1.6\times$​​ ${10}^{8}m{s}^{-1}$

Answer 1

The correct option is A

$2.25\times$​​ ${10}^{8}m{s}^{-1}$

The speed of light in water is reduced by a factor of 1.33 which means the speed of light in water is $\frac{3\times {10}^8}{1.33}$​ $=2.25\times {10}^{8}m{s}^{-1}$