Area of the recangualr ciol = A:

\(\displaystyle{A}={5}{c}{m}\times{8}{c}{m}=\frac{{40}}{{10000}}={0.004}{m}^{{{2}}}\)

Let , the rate of change of magnetic field is : d B / dt = ?

current = I = 0.1 A

resitence = R = 8 ohms

thus, amount of induced emf in would be

\(\displaystyle{e}={I}{R}={0.1}\times{8}={0.8}{v}{o}{<}\)

No. of turns of the coil = N = 75 turns

It is known by the formula for

Induced emf is :

e = A N dB / dt

thus, d B / dt = e / N A

\(\displaystyle=\frac{{0.8}}{{75}}\times{0.004}\)

= 0.8 / 0. 3

= 2.7 T /s (2.666666667)