The primary and secondary coils of a transmformer have `50` and `1500` turns respectively. If the magnetic flux `phi` linked with the primary coil is given by `phi=phi_(0)+4t`, where `phi` is in weber, `t` is time in second and `phi_(0)` is a constant, the output voltage across the secondary coil is

Options

A. 30 volts
B. 90 volts
C. 120 volts
D. 220 volts

Answer

C

Explanation

Induced emf in primary coil `E_(p)=(dphi)/(dt)=(d)/(dt)(phi_(0)+4t)=4`volt
Induced emf in secondary coil
`(E_(S))/(E_(P))=(N_(S))/(N_(P))implies(E_(S))/(4)=(1500)/(50)implies E_(S)=120` volt