Question

The speed of light in a medium of refractive index 2 is?

• A. $1.5\times {10}^{8}m/s$
• B. $1.5\times {10}^{6}m/s$
• C. $6.67\times {10}^{7}m/s$
• D. $3\times {10}^{8}m/s$

Answer 1

The correct option is A $1.5\times {10}^{8}m/s$

Given: Speed of light in air, $c=3\times {10}^{8}m/s$
Refractive index, μ = 2
Also, $\mu =\frac{c}{v}$$\Rightarrow v=\frac{c}{\mu }=\frac{3\times {10}^8}{2}$$\Rightarrow v=1.5\times {10}^{8}m/s$
Hence, the correct answer is option (1).