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 $II$ is
  • A
    from $a$ to $b$ and from $c$ to $d$
  • from $b$ to $a$ and from $c$ to $d$
  • C
    from $b$ to $a$ and from $f$ to $e$
  • D
    from $a$ to $b$ and from $d$ to $c$

Answer

Correct option: B.
from $b$ to $a$ and from $c$ to $d$
b
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 $B$ is decreasing so $B_{\in \text { duce }}$ will be $\otimes$ therefore option $C$ is correct.

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