A 100 % efficient transformer has 1500 turns on its primary coil. The input to the transformer is 250V ac. The output current is 10A and the output power is 0.5 kW. is the number of turns on the secondary coil?

Answer:

7) 300

Let number of turns on primary coil be = N1 = 1500
Let number of turns on secondary coil be = N2
Input voltage = V1 = 250V
Output voltage = V2 = P/I = (0.5×1000)/10 = 50 V

Formula:

N1 = N2
V1    V2

1500 = N2
 250     50

N2 = 300