The magnetic field in a region between the poles of an electromagnet is uniform at any time, but its magnitude is increasing at the rate of 0.02 T/s . A conducting loop is placed in this region, whose plane is perpendicular to the direction of magnetic field. Calculate the emf induced and induced current in the loop. Take cross-section area of loop as 120 cm2 and resistance of loop as 5Ω .

Question

The magnetic field in a region between the poles of an electromagnet is uniform at any time, but its magnitude is increasing at the rate of 0.02 T/s . A conducting loop is placed in this region, whose plane is perpendicular to the direction of magnetic field. Calculate the emf induced and induced current in the loop. Take cross-section area of loop as 120 cm2 and resistance of loop as 5Ω . (A) 0.48 V, 0.0096 mA (B) 0.48 mV, 0.0096 mA (C) 0.24 mV, 0.048 mA (D) 0.24 mV, Zero

Tardigrade Admin · Accepted Answer

Induced emf e=-(d φ/d t)=-A × (d B/d t) =-120 × 10-4 × 0.02 Negative sign tells about the direction (polarity). Also, i=(e/R)=(0.24/5) =0.048 m A

0.48 V, 0.0096 mA

0.48 mV, 0.0096 mA

0.24 mV, 0.048 mA

0.24 mV, Zero

Induced emf e=−dtdϕ​=−A×dtdB​ =−120×10−4×0.02 Negative sign tells about the direction (polarity). Also, i=Re​=50.24​ =0.048mA

Induced emf
$e = - \frac{d ϕ}{d t} = - A \times \frac{d B}{d t}$
$= - 120 \times 1 0^{- 4} \times 0.02$
Negative sign tells about the direction (polarity).
Also, $i = \frac{e}{R} = \frac{0.24}{5}$
$= 0.048 m A$