MCQ
The adjoining figure shows two different arrangements in which two square wire frames are placed in a uniform constantly decreasing magnetic field $B.$ The direction of induced current in the case $I$ is
  • A
    from $a$ to $b$ and from $c$ to $d$
  • B
    from $a$ to $b$ and from $f$ to $e$
  • from $b$ to $a$ and from $d$ to $c$
  • D
    from $b$ to $a$ and from $e$ to $f$

Answer

Correct option: C.
from $b$ to $a$ and from $d$ to $c$
c
$Case\, I,$ $I=\frac{1}{R} \frac{d \phi}{d t}=\frac{\left(L^{2}+l^{2}\right)}{R} \frac{d B}{d t}$

since $\mathrm{B}$ is decreasing so$B_{\text {duce}} will \, be \otimes$ therefore option $C$ is correct.

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