Physics - EMI/AC Question with Solution | TestHub

Induced emf,
${\rm E}=-\frac{d\varphi }{dt}$
Therefore,${\rm E}=0$when$\frac{d\varphi }{dt}=0$and vice versa.
Even if$\varphi =0,\frac{d\varphi }{dt}$may be non-zero.
Similarly, if$\varphi \ne 0,\frac{d\varphi }{dt}$may be zero.
For example, if$\varphi ={\varphi }_0\mathrm{s}\mathrm{i}\mathrm{n}\left(\omega t\right)$
Then,${\rm E}=-\frac{d\varphi }{dt}=-{\varphi }_0\mathrm{c}\mathrm{o}\mathrm{s}\left(\omega t\right)$