Question

In a coil of resistance 150 `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 ____________.

Options

• 750 Wb

• 275 Wb

• 200 Wb

• 225 Wb

Answer 1

In a coil of resistance 150 `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 750 Wb.

Explanation:

`abs"e" = ("d"phi)/"dt"`

`"iR" = ("d"phi)/"dt"`

`therefore int"d"phi = "R" int "I"  "dt"`

This means

`abs(dphi) = "Resistance x area under current - time graph"`

`= 150 xx 1/2 xx 20 xx 0.5`

` = 750  "Wb"`