Question

The magnetic flux through a coil containing 50 loops changes from 30 Wb to –30 Wb in 0.42 seconds. What is the voltage induced in the coil?

Answer 1

I would use Farady´s Law and the fact that:
Induced emf `V_(i.n.d)=-N(Delta(Phi))/(Deltat)`
Where:
`N`= number of turns;
`Phi`= magnetic flux.
So:`V_(i.n.d)=-50(-30-30)/0.42=7143V`