Find the ratio of product of velocity and time period of electron orbiting in 2nd and 3rd stable orbits.

Explanation

To find the ratio of the product of velocity and time period of an electron orbiting in the 2nd and 3rd stable orbits, we can follow these steps:

### Step 1: Understand the relationships
We know from atomic physics that:
- The time period \( T_n \) of an electron in the nth orbit is proportional to \( n^3 \):
\[ T_n \propto n^3 \]
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