Electro Magnetic Induction And Alternating Currents Question 379
Question: A coil of 40 W resistance has 100 turns and radius 6 mm is connected to ammeter of resistance of 160 ohms. Coil is placed perpendicular to the magnetic field. When coil is taken out of the field, 32 m C charge flows through it. The intensity of magnetic field will be [RPET 1997]
Options:
A) 6.55 T
B) 5.66 T
C) 0.655 T
D) 0.566 T
Show Answer
Answer:
Correct Answer: D
Solution:
$ q=-\frac{N}{R}( B_{2}-B_{1} )A\cos \theta $ $ 32\times {{10}^{-6}} $ $ =-\frac{100}{( 160+40 )}( 0-B )\times \pi \times {{( 6\times {{10}^{-3}} )}^{2}}\times \cos 0^{o} $
$ \Rightarrow B=0.565\ T $