A wire of resistivity `rho` is stretched to double its length. What is its new resistivity ?

Explanation

To solve the problem of finding the new resistivity of a wire when it is stretched to double its length, we can follow these steps:

### Step 1: Understand the Concept of Resistivity
Resistivity (ρ) is a property of the material that does not change with the shape or size of the material. It is defined as the resistance of a unit length of a material with a unit cross-sectional area.

### Step 2: Identify the Given Information
- Initial resistivity of the wire: ρ
- The wire is stretched to double its length: L' = 2L
...