Magnetic Effects Of Current Question 73
Question: The magnetic field at a distance r from a long wire carrying current i is 0.4 Tesla. The magnetic field at a distance 2r is [CBSE PMT 1992; DPMT 2004]
Options:
A) 0.2 Tesla
B) 0.8 Tesla
C) 0.1 Tesla
D) 1.6 Tesla
Show Answer
Answer:
Correct Answer: A
Solution:
$ B=\frac{{\mu_{0}}i}{2\pi r},i.e.B\propto \frac{1}{r}i.e. $ when $ r $ is doubled, $ B $ is halved.
BETA
