The ratio of velocity of light in first medium to that of velocity of light in second medium is _____

Explanation

To solve the question regarding the ratio of the velocity of light in the first medium to that in the second medium, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Concept of Refractive Index**:
The refractive index (n) of a medium is defined as the ratio of the speed of light in vacuum (c) to the speed of light in that medium (v). Mathematically, it is expressed as:
\[
n = \frac{c}{v}
...