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6. Electromagnetic induction — Physics STD 12 Science — Question

CBSE BoardEnglish MediumSTD 12 SciencePhysics6. Electromagnetic induction1 Mark
MCQ
A coil and a bulb are connected in series with a $12 \,volt$ direct current source. A soft iron core is now inserted in the coil. Then
  • ✓
    The intensity of the bulb remains the same
  • B
    The intensity of the bulb decreases
  • C
    The intensity of the bulb increases
  • D
    Nothing can be said
✓

Answer

Correct option: A.
The intensity of the bulb remains the same
a
(a)

Intensity of bulb remains the same because source is $D C$, so steady state current will be independent of the inductance of the inductor for $D C$ circuit,

$i_{\text {stoady }}=\frac{E_{\text {source }}}{R_{\text {bubb }}}$

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