Paheli had heard that rain water is as good as distilled water. So, she collected some rain water in a clean glass tumbler and tested it using a tester. To her surprise, she found that the compass needle showed deflection. What could be the reasons?

Explanation

To analyze why Paheli found deflection in the compass needle when testing rainwater with a tester, we can break down the explanation step by step:

### Step-by-Step Solution:

1. **Understanding Rainwater Composition**:
- Rainwater is not pure; it often contains dissolved substances, including salts and minerals. These substances dissociate into ions when dissolved in water.

2. **Testing with a Tester**:
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