Magnetism Question 201
Question: Two like magnetic poles of strength 10 and 40 SI units are separated by a distance 30 cm. The intensity of magnetic field is zero on the line joining them
[JIPMER 1999]
Options:
A) At a point 10 cm from the stronger pole
B) At a point 20 cm from the stronger pole
C) At the mid-point
D) At infinity
Show Answer
Answer:
Correct Answer: B
Solution:
Suppose magnetic field is zero at point P. Which lies at a distance x from 10 unit pole. Hence at P $ \frac{{\mu _{0}}}{4\pi }.\frac{10}{x^{2}}=\frac{{\mu _{0}}}{4\pi }.\frac{40}{{{( 30-x )}^{2}}}\Rightarrow x=10cm $ So from stronger pole distance is 20 cm.
BETA
