An electric iron is based upon the principle of

Options

A. heating effect of current
B. magnetic effect of current
C. chemical effect of current
D. none of these

Answer

**Step-by-Step Solution:**

1. **Understanding the Electric Iron's Structure:**
- An electric iron consists of a metal plate, a mica sheet, and a coil of wires. The coil is responsible for generating heat when electric current passes through it.

2. **Current Flow and Heat Generation:**
- When electric current flows through the coil of wires, it generates heat due to the resistance of the wire. This can be expressed by the formula for heat produced in a conductor:
\[ Q = I^2 R t \]
where \( Q \) is the heat produced, \( I \) is the current, \( R \) is the resistance, and \( t \) is the time.

3. **Heat Transfer:**
- The heat generated in the coil is transferred through the mica sheet to the metal plate below. Mica is chosen because it is a good conductor of heat but a poor conductor of electricity, preventing any electric current from passing through the metal plate.

4. **Safety Considerations:**
- The use of mica ensures that while heat is transferred to the metal plate, the risk of electric shock is minimized, as no current flows through the metal.

5. **Conclusion:**
- The principle on which an electric iron operates is primarily based on the heating effect of electric current. Therefore, the correct answer to the question is that an electric iron is based upon the "heating effect of current."

**Final Answer:**
An electric iron is based upon the principle of the heating effect of current.

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