Question

Yash made his own electromagnet but he found that it is not sufficiently strong. So, what are the possible way(s) that he should use to make the electromagnet strong?
(i) Decrease the number of turns in the coil.
(ii) Increase the current in the coil.
(iii) Use a plastic core inside the coil.
(iv) Reverse the current direction in the coil.

• A. (i) and (iv) only
• B. (i), (ii), and (iii)
• C. (i), (ii) , and (iv)
• D. (ii) only

Answer 1

The correct option is D (ii) only

The strength of an electromagnet can be increased by:
1. Increasing the current in the coil
2. Increasing the number of turns in the coil
3. Using a soft iron core inside the coil.
Reversing the current in the coil will only change the polarity of the electromagnet but its strength remains the same.