Question

In a coil of resistance $100 \, \Omega$, a current is induced by changing the magnetic flux through it as shown in the figure. The magnitude of change in flux through the coil is :

• A. 200 Wb
• B. 225 Wb
• C. 250 Wb
• D. 275 Wb

Answer 1

Answer: (C)

250 Wb

Answer 2

$\varepsilon = \frac{d\phi}{dt}$
$iR = \frac{d\phi}{dt}$
$\int d\phi = R \int idt$
Magnitude of change in flux = R $\times$ area under current vs time graph
$= 100 \times \frac{1}{2} \times \frac{1}{2} \times 10$
$= 250 \, Wb$