A 100 % efficiency transformer has 100 turns in the primary and 25 turm coil. If the current in the secondary coil is 4 A, then the current in the primary coil is
Number of turns in the primary , Np = 100
Number of turns in the secondary , Ns = 25
Current in the secondary coil ,Is = 4 amp
we have to find out current in the primary coil ,Ip = ?
∵ Ns/Np = Vs/Vp
Also , Vs × is = Vp × ip
Then, Ns/Np = Ip/is
⇒100/25 =Ip/4
⇒4 × 4 = Ip
⇒ Ip = 16 amp