91Ó°ÊÓ

The magnetic flux is the measure of magnetic force that passes through the coil of area A. The magnetic flux is generated by when magnetic force is parallel to the plane's normal.

${\mathrm{Φ}}_m=BA$

The diameter of the coil is d = 1 cm. So, the area of the coil is

$A=\mathrm{π}{\left(\frac{d}{2}\right)}^2=\mathrm{π}{\left(\frac{1×{10}^{−2}\mathrm{m}}{2}\right)}^2=7.85×{10}^{−5}{\mathrm{m}}^2$

The change in the flux is,

$d{\mathrm{Φ}}_m=BA$

The induced emf, as stated by Faraday's law, is the change in magnetic flux inside the coil, and it is determined by equation (30.14) in the form

$\mathrm{Î\mu }=N\frac{d{\mathrm{Φ}}_{\mathrm{m}}}{dt}=\frac{NBA}{dt}$

From Ohm's law, we can get the induced current by

Capacitance of the capacitor with time $I=dq/qt$

The charge and capacitance C of the capacitor are determined by the potential difference across the capacitor.

$\mathrm{Δ}{V}_C=\frac{dq}{C}=\frac{NBA}{RC}$

Now, we plug the values for N, B, A, R and C

$\mathrm{Δ}{V}_C=\frac{NBA}{RC}$

$=\frac{\left(10\right)\left(1×{10}^{−3}\mathrm{T}\right)\left(7.85×{10}^{−5}{\mathrm{m}}^2\right)}{\left(0.2\mathrm{Î\copyright }\right)\left(1×{10}^{−6}\mathrm{F}\right)}$

$=3.9\mathrm{V}$