Why does rubber become stiff on stretching?

Explanation

**Step-by-Step Text Solution:**

1. **Understanding the Structure of Rubber:**
- Rubber is made up of long, coiled polymer chains. In its unstretched state, these chains are arranged in a way that allows for flexibility and movement.

2. **Molecular Interaction in Unstretched Rubber:**
- In the unstretched form, the intermolecular forces between the rubber molecules are relatively weak. This allows the rubber to be elastic and stretchable.

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