A conducting circular loop of radius (10/√π) 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:

Question

A conducting circular loop of radius (10/√π) 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: (A) emf =1 mV (B) emf =100 mV (C) emf =5 mV (D) emf =10 mV

Tardigrade Admin · Accepted Answer

EMF =( d φ/ dt )=( BA -0/ t ) A =π r 2=π((0.12/π))=0.01 B =0.5 EMF =((0.5)(0.01)/0.5)=0.01 V =10 mV

Q. A conducting circular loop of radius $\frac{10}{π} c m$ 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:

$e m f = 1 mV$

$e m f = 100 mV$

$e m f = 5 mV$

$e m f = 10 mV$

$EMF = \frac{d ϕ}{d t} = \frac{B A - 0}{t}$
$A = π r^{2} = π (\frac{0. 1 ^{2}}{π}) = 0.01$
$B = 0.5$
$EMF = \frac{( 0.5 ) ( 0.01 )}{0.5} = 0.01 V = 10 mV$

Q. A conducting circular loop of radius π​10​cm is placed perpendicular to a uniform magnetic field of 0.5T. The magnetic field is decreased to zero in 0.5s at a steady rate. The induced emf in the circular loop at 0.25s is:

emf=1mV

emf=100mV

emf=5mV

emf=10mV