The transformer supplying power to an artist's light sculpture provides 9600-V AC when supplied by 120-V AC. If there are 100 turns in the transformer's primary coil, how many turns are there in its secondary coil

1.25 turns

Explanation:

From Transformer equation,

Ns/Np = Vs/Vp Equation 1

Where Ns = Secondary turns, Np = Primary turns, Vs = secondary Voltage, Vp = Primary Voltage.

make Ns the subject of the equation  1

Ns = NpVs/Vp Equation 2

Given: Np = 100 turns, Vp = 120 V, Vs = 9600 V

Substitute into equation 2

Ns = 100(120)/9600

Ns = 1.25  turns.

Hence the are 1.25 turns in the  secondary coil = 1.25 turns