Electromagnetic Induction Question 1
Question 1 - 24 January - Shift 1
A conducting loop of radius $\frac{10}{\sqrt{\pi}} cm$ is placed perpendicular to a uniform magnetic field of $0.5 T$. The magnetic field is decreased to zero in $0.5 s$ at a steady rate. The induced emf in the circular loop at 0.25 s is:
(1) $emf=1 mV$
(2) $emf=10 mV$
(3) $emf=100 mV$
(4) $emf=5 mV$
Show Answer
Answer: (2)
Solution:
Formula: Faraday’s Laws Of Electromagnetic Induction
$EMF=\frac{d \phi}{dt}=\frac{BA-0}{t}$
$A=\pi r^{2}=\pi(\frac{0.1^{2}}{\pi})=0.01$
$B=0.5$
$EMF=\frac{(0.5)(0.01)}{0.5}=0.01 V=10 mV$