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Standard XII

Physics

Motional EMF

The current i...

Question

The current in a coil of 0.4 mH coil increases by 250 mA in 0.1 seconds. The induced emf will be:-

+1 V

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-1 V

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+ 1 mV

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-1 mV

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Solution

The correct option is D -1 mV
Fig: Inductor circuit

The emf induced in inductor i,
$ε = - L \frac{d I}{d t}$
Given,
$L = 0.4 m H$
$d I = 250 m A$
$d t = 0.1 s e c$
$ε = - \frac{0.4 \times 10^{- 3} \times 250 \times 10^{- 3}}{0.1}$
$ε = - 1 m V$
The correct Option is $D$

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The current in a coil of 0.4 mH coil increases by 250 mA in 0.1 seconds. The induced emf will be:-

The correct option is D -1 mV Fig: Inductor circuitThe emf induced in inductor i, ε=−LdIdtGiven,L=0.4mHdI=250mAdt=0.1secε=−0.4×10−3×250×10−30.1ε=−1mVThe correct Option is D

The correct option is D -1 mV
Fig: Inductor circuit

The emf induced in inductor i,
$ε = - L \frac{d I}{d t}$
Given,
$L = 0.4 m H$
$d I = 250 m A$
$d t = 0.1 s e c$
$ε = - \frac{0.4 \times 10^{- 3} \times 250 \times 10^{- 3}}{0.1}$
$ε = - 1 m V$
The correct Option is $D$