Concept:Faraday's Law, combined with Lenz's Law, calculates both the magnitude and polarity of the induced voltage.
Formula:$$ \varepsilon = -N \frac{\Delta \phi}{\Delta t} $$
Solution:- Given: Number of turns \( N = 100 \).
- Change in flux \( \Delta \phi = 2 \times 10^{-4} \text{ Wb} \).
- Time interval \( \Delta t = 0.02 \text{ s} = 2 \times 10^{-2} \text{ s} \).
- Substitute values into the formula:
$$ \varepsilon = -100 \times \frac{2 \times 10^{-4}}{2 \times 10^{-2}} $$
- Simplify the fraction:
$$ \varepsilon = -100 \times (1 \times 10^{-2}) $$
- Solve:
$$ \varepsilon = -100 \times 0.01 = -1.0 \text{ V} $$
Why other options are incorrect:Option A misses the negative sign dictated by Lenz's law. Options C and D stem from failing to convert the decimal \( 0.02 \) correctly when managing the exponents.
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