An electric iron of resistance `20 Omega` takes a current of `5 A`. Calculate the heat developed in `30 s`.

Explanation

To solve the problem of calculating the heat developed by an electric iron with a resistance of 20 ohms and a current of 5 A over a period of 30 seconds, we can use the formula for electrical heat energy:

### Step-by-Step Solution:

1. **Identify the given values:**
- Resistance (R) = 20 ohms
- Current (I) = 5 A
- Time (T) = 30 seconds
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