Question

What is the induced EMF in the primary coil?

Options

• \[e_p=N_p\Phi\]

• \[e_p=-N_s\frac{d\Phi}{dt}\]

• \[e_p=-N_p\frac{d\Phi}{dt}\]

• \[e_p=-N_p\frac{dt}{d\Phi}\]

Answer 1

Faraday's Law gives the primary EMF as \[e_p=-N_p\frac{d\Phi}{dt}\]. The expression uses the number of primary turns and the rate of change of flux.