Physics

Problem

The magnetic flux linked with a 200-turn coil is given by

\Phi_B(t)=\begin{cases}3t^2\;\text{Wb}, & 0\le t\le 2\;\text{s}\\12t-12\;\text{Wb}, & t>2\;\text{s}\end{cases}

(i) Write the expression for the induced emf

\mathcal E(t)

for the entire interval

0\le t\le6\;\text{s}

. (ii) Calculate the magnitude of the emf at

t=1\;\text{s}

and at

t=4\;\text{s}