Question

The heating element of an electric iron is made up of

• A. copper
• B. nichrome
• C. aluminum
• D. iron

Answer 1

The correct option is B

nichrome

Explanation for correct answer:

• Option B: Nichrome

1. Nichrome is an alloy of nickel $(80\%)$ and chromium $(20\%)$.
2. It has a high melting point of $1400°C$.
3. When heated for the first time, it forms an adherent layer of chromium oxide.
4. Because the material beneath this layer will not oxidize, the wire will not break or burn out.
5. As a result, nichrome is used as a heating element.
6. Hence, option B is correct.

Explanation for incorrect answer:

• Option A: Copper

1. Copper is a good electrical conductor with low resistance.
2. Low resistance provides less heating.
3. As a result, copper is not used in heating coils.
4. Hence, option A is not correct.

• Option C: Aluminum

1. Aluminum is a good conductor with low resistivity, but it is inefficient at converting electrical energy to heat energy.
2. Hence, option C is not correct.

• Option D: Iron

1. Iron is a good heat and electricity conductor because of this the wire will break or burn out.
2. Hence, option D is not correct.

Thus, option B is the correct answer.