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6. Electromagnetic induction — Physics STD 12 Science — Question

CBSE BoardEnglish MediumSTD 12 SciencePhysics6. Electromagnetic induction1 Mark
MCQ
Figure shows a conducting loop placed in magnetic field. The flux through the loop changes due to change in magnetic field according to the equation $\phi  = 5t - 10{t^2}$. What is direction and magnitude of induced current at $t = 0.25\, s$ ?
  • A
    $0.5\,A,\, A\to B$
  • B
    $0.5\,A,\, B\to A$
  • C
    $1.5\,A,\, A\to B$
  • ✓
    Zero
✓

Answer

Correct option: D.
Zero
d
$\mathrm{Emf}=\frac{-\mathrm{d} \phi}{\mathrm{dt}}=-[5-20 \mathrm{t}]=-\left[5-20 \times \frac{1}{4}\right]=0$

Induced current $=0$

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