A current .I. flows through a metallic wire of radius .r. and the free electrons in it drift with a velocity `v_(d)`. Calculate the drift velocity of the free electrons through the wire of the same material, having double the radius, when same current flows through it.

Explanation

To solve the problem of calculating the drift velocity of free electrons in a wire with double the radius while maintaining the same current, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the relationship between current, charge density, area, and drift velocity:**
The current \( I \) flowing through a wire can be expressed as:
\[
I = n \cdot A \cdot e \cdot v_d
...