A voltmeter resistance `500 Omega` is used to measure the emf of a cell of internal resistance `4 Omega`. The percentage error in the reading of the voltmeter will be

Explanation

To find the percentage error in the reading of the voltmeter when measuring the emf of a cell with internal resistance, we can follow these steps:

### Step-by-Step Solution

1. **Identify the Given Values**:
- Resistance of the voltmeter, \( R_v = 500 \, \Omega \)
- Internal resistance of the cell, \( r = 4 \, \Omega \)

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