Magnetism Question 119
Question: A tangent galvanometer has a coil of 25 turns and radius of 15 cm. The horizontal component of the earth’s magnetic field is 3 ´ 10?5 T. The current required to produce a deflection of 45o in it, is
[MP PMT 2000]
Options:
A) 0.29 A
B) 1.2 A
C) 3.6 ´ 10?5 A
D) 0.14 A
Show Answer
Answer:
Correct Answer: A
Solution:
$ i=\frac{2rB _{H}}{{\mu _{0}}N}\tan \theta $
$ \Rightarrow i=\frac{2\times 15\times {{10}^{-2}}\times 3\times {{10}^{-5}}}{4\pi \times {{10}^{-7}}\times 25}\times \tan 45^{o} $
$ \Rightarrow i=0.29\ A $
BETA
