Q 12-06-091JEE MainJEE Main 2022 (26 Jun, Shift 1)Easy
The magnetic flux through a coil perpendicular to its plane is varying according to the relation $\phi = (5t^3 + 4t^2 + 2t - 5)$ weber. If the resistance of the coil is $5\ \text{ohm}$, then the induced current through the coil at $t = 2\ \text{s}$ will be
Answer: (A) $15.6\ \text{A}$
$|\varepsilon| = \dfrac{d\phi}{dt} = 15t^2 + 8t + 2 = 60 + 16 + 2 = 78\ \text{V}$ at $t = 2\ \text{s}$.
$$I = \frac{78}{5} = 15.6\ \text{A}$$
Solution by Sreeraj P, M.Sc Physics