The magnetic flux linked to a coil changes from \( 10 \times 10^{-3}\,\mathrm{Wb} \) to \( 6 \times 10^{-3}\,\mathrm{Wb} \) in 0.01 s. The induced emf will be:
Answer & explanation
Correct answer: option 2
The correct answer is Option (2) → 0.4 V
By Faraday's law of electromagnetic induction, the magnitude of the induced emf equals the rate of change of magnetic flux.
\( \displaystyle |\varepsilon| = \frac{\Delta\phi}{\Delta t} \)
\( \displaystyle \Delta\phi = 10\times10^{-3} - 6\times10^{-3} = 4\times10^{-3}\,\mathrm{Wb} \)
\( \displaystyle |\varepsilon| = \frac{4\times10^{-3}\,\mathrm{Wb}}{0.01\,\mathrm{s}} = 0.4\,\mathrm{V} \)