Some magnetic flux is changed from a coil of resistance `10 Omega`. As a result, an induced current is developed it, which varies with time as shown in Fig. Find the magnitude of the change in flux through the coil in weber.

Options

A. 2
B. 4
C. 6
D. none of these

Answer

A

Explanation

From `dq = I dt = (dphi)/(R )`
`d phi = (I dt) R`
`= ("area under I = t graph") xx R`
`= ((1)/(2) xx 4 xx 0.1) xx 10 = 2 web`