Question

The magnetic flux through a coil perpendicular to its plane is varying according to the relation \( \phi = 5t^3 + 4t^2 + 2t - 5 \). If the resistance of the coil is \( 5 \, \Omega \), then the induced current through the coil at \( t = 2 \, \text{sec} \) will be:

• A. \( 15.6 \, \text{A} \)
• B. \( 16.6 \, \text{A} \)
• C. \( 17.6 \, \text{A} \)
• D. \( 18.6 \, \text{A} \)

Hint:

Always differentiate the magnetic flux \( \phi \) with respect to time \( t \) to calculate the induced EMF, and use \( i = \frac{e}{R} \) to determine the current.