Appliances based on heating effect of current work on

Options

A. only d.c.
B. only a.c.
C. both d.c. and a.c.
D. none of these

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the type of current (AC or DC) that appliances based on the heating effect of current can work on.

2. **Heating Effect of Current**: Appliances that utilize the heating effect of current convert electrical energy into heat energy. This effect is described by the formula \( H = I^2Rt \), where:
- \( H \) is the heat produced,
- \( I \) is the current,
- \( R \) is the resistance, and
- \( t \) is the time for which the current flows.

3. **Analyzing the Formula**: In the formula \( H = I^2Rt \), we can see that the heat produced depends on the square of the current (\( I^2 \)), the resistance (\( R \)), and the time (\( t \)).

4. **Nature of Current**: The formula does not specify whether the current is alternating (AC) or direct (DC). This indicates that the heating effect is independent of the type of current used.

5. **Conclusion**: Since the heating effect of current does not depend on whether the current is AC or DC, we can conclude that appliances based on the heating effect of current can work on both AC and DC.

6. **Final Answer**: Therefore, the correct answer is that appliances based on the heating effect of current work on both AC and DC.

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