Define refractive index of a tranparent medium . The speed of light in a medium of absolute refractive index ` 1.5 " is " 2xx10^(8)ms^(-1)` . What is the speed of light in vacuum ?

Explanation

### Step-by-Step Solution:

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

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