Magnetism Question 170
Question: Points A and B are situated perpendicular to the axis of a 2cm long bar magnet at large distances X and 3X from its centre on opposite sides. The ratio of the magnetic fields at A and B will be approximately equal to
[CPMT 1988]
Options:
A) 1 : 9
B) 2 : 9
C) 27 : 1
D) 9 : 1
Show Answer
Answer:
Correct Answer: C
Solution:
$ B\propto \frac{1}{x^{3}}\Rightarrow \frac{B _{1}}{B _{2}}={{( \frac{x _{2}}{x _{1}} )}^{3}}={{( \frac{3x}{x} )}^{3}}=\frac{27}{1} $
BETA
