The magnetic flux through a coil perpendicular to its plane is varying according to the relation $\phi = (5{t^3} + 4{t^2} + 2t - 5)$ Weber. If the resistance of the coil is 5 ohm, then the induced current through the coil at t = 2 s will be,
Solution
$\phi=5 \mathrm{t}^3+4 \mathrm{t}^2+2 \mathrm{t}-5$
<br/><br/>$|\mathrm{e}|=\frac{\mathrm{d} \phi}{\mathrm{dt}}=15 \mathrm{t}^2+8 \mathrm{t}+2$
<br/><br/>At $\mathrm{t}=2,|\mathrm{e}|=15 \times 2^2+8 \times 2+2$
<br/><br/>$\Rightarrow \mathrm{e}=78 \mathrm{~V} $
<br/><br/>$\Rightarrow \mathrm{I}=\frac{\mathrm{e}}{\mathrm{R}}=\frac{78}{5}=15.60$
About this question
Subject: Physics · Chapter: Electromagnetic Induction · Topic: Faraday's Laws
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