Moving Charges and Magnetism - Result Question 50
51. A straight wire of diameter $0.5 mm$ carrying a current of $1 A$ is replaced by another wire of 1 $mm$ diameter carrying same current. The strength of magnetic field far away is
[1995, 97, 99]
(a) twice the earlier value
(b) same as the earlier value
(c) one-half of the earlier value
(d) one-quarter of the earlier value
Show Answer
Answer:
Correct Answer: 51. (b)
Solution:
- (b) $B=\frac{\mu_0 i}{2 \pi r}$ and so it is independent of thickness.
The current is same in both the wires, hence magnetic field induced will be same.