Physics - EMI/AC Question with Solution | TestHub

As a constant magnetic field conducting ring oscillates with a frequency of $100\mathrm{Hz}$. i.e. $T=\frac{1}{100}\mathrm{s}$, for $\frac{T}{2}$, it goes up to $B$ $\therefore$ The corresponding frequency is $200\mathrm{Hz}$. $$\begin{array}{rl}& \text{ Induced emf }=\frac{\text{ change in flux }}{\text{ time }}\\ & =\frac{2BA\cos \theta }{T}=2BAf\cos \theta \\ & =\pi r^2\times 2\times 0.01\times 200\text{ as }r=1\mathrm{m}\\ & =\pi 1^2\times 2\times 0.01\times 200=4\pi \mathrm{V}.\end{array}$$
Non-electrostatic induced electric field along the circle, $$E=\frac{1}{2\pi r}\times \left(\pi r^2\times \frac{dB}{dt}\right)=\frac{e}{2\pi r}=\frac{4\pi }{2\pi r}=2\mathrm{V}/\mathrm{m}.$$