• # question_answer In the circuit shown the cell is ideal. The coil has an inductance of 4H and zero resistance. F is a fuse of zero resistance and will blow when the current through it reaches 5A. The switch is closed at t = 0. The fuse will blow- A) After 5 sec B) After 2 sec C) After 10 sec D) Just after closing of S

[C]  Applying Kirchoff voltage law $E=L\frac{di}{dt}$ Where E=2V and L=4H $di=\frac{E}{L}dt$ $\int\limits_{0}^{i}{\,di=\int\limits_{0}^{t}{\frac{E}{L}dt}}$
 $i=\frac{E}{L}t$ $i=\frac{2}{4}t=0.5t$ $i=0.5\,\,t$ Fuse will blow when i become 5A So 5=0.5 t $t=10\sec$ After 10 sec F will blow