Question

4. The primary coil of a transformer has 225 turns and secondary coil has 1800 turns. The potential difference in the primary coil is 250 V and the power input is 3 600 W. (Please show steps)

a) Is this a step-up or step-down transformer?

b) What is the current in the primary coil?

c) What is the power in the secondary coil?

d) What is the potential difference in the secondary coil?

e) What is the current in the secondary coil?

Answer 1

A.) Step up transformer

B.) 14.4 A

C.) 3600W

D.) 1.8 A

Explanation: Given that the

Np = 225 turns

Ns = 1800 turns.

Vp = 250 V

Power input = 3 600 W.

A.) Since the number of turn of coil at the secondary is more than the primary side, It is a step up transformer.

B.) Since the input power is equal to 3600W, let's use power formula

P = IV

3600 = 250I

Make the current I the subject of formula

I = 3600/250

I = 14.4 Ampere

C.) Power in the secondary coil will be the same as input power. Because power is always constant. Therefore,

Power P = 3600W

D.) From transformer formula,

Np/Ns = Is/IP

225/1800 = Is/14.4

Cross multiply

1800Is = 3240

Is = 3240/1800

Is = 1.8 A