The difference of speed of light in the two media A and B (v_A -v_B ) is 2.6 × 10^7 m / s. If the refractive index of medium B is 1.47, then the…

The difference of speed of light in the two media A and B $\displaystyle \left(v_{\mathrm{A}}-v_{\mathrm{B}}\right)$ is $\displaystyle 2.6 \times 10^7 \mathrm{~m} / \mathrm{s}$. If the refractive index of medium $\displaystyle B$ is $\displaystyle 1.47$ , then the ratio of refractive index of medium $\displaystyle B$ to medium A is : (Given : speed of light in vacuum $\displaystyle \mathrm{c}=3 \times 10^8 \mathrm{~ms}^{-1}$ )