JEE PYQ: Electromagnetic Induction Question 12
Question 12 - 2020 (08 Jan Shift 1)
At time $t = 0$ magnetic field of 1000 Gauss is passing perpendicularly through the area defined by the closed loop shown in the figure. If the magnetic field reduces linearly to 500 Gauss, in the next 5 s, then induced EMF in the loop is:
The loop is rectangular (16 cm by 4 cm) with two triangular cutouts (base 2 cm, height 4 cm).
(1) 56 $\mu$V
(2) 28 $\mu$V
(3) 48 $\mu$V
(4) 36 $\mu$V
Show Answer
Answer: (1)
Solution
$\frac{dB}{dt} = \frac{1000 - 500}{5} \times 10^{-4} = 10^{-2}$ T/s. Area $A = (16 \times 4 - 2 \times \frac{1}{2} \times 2 \times 4)$ cm$^2 = (64 - 8) = 56$ cm$^2 = 56 \times 10^{-4}$ m$^2$. EMF $= A \times \frac{dB}{dt} = 56 \times 10^{-4} \times 10^{-2} = 56 \times 10^{-6}$ V $= 56;\mu$V.
BETA
