Question

A transformer has 132 kV across its primary coil and 33 kV across the secondary coil. It produces a current of 8 A in its secondary coil. How much current flows through the primary coil? [4 marks]

Answer 1

32 A.

Step-by-step explanation:

In a transformer, the ratio of the voltage across the primary coil to the voltage across the secondary coil is equal to the ratio of the current in the primary coil to the current in the secondary coil. This relationship is known as the transformer equation, and it can be written as follows:

Vp / Vs = Is / Ip

Where Vp is the voltage across the primary coil, Vs is the voltage across the secondary coil, Is is the current in the secondary coil, and Ip is the current in the primary coil.

Given the values provided in the problem, we can substitute them into the transformer equation to find the current in the primary coil:

Ip = (Vp * Is) / Vs

= (132 kV * 8 A) / 33 kV

= 32 A

Therefore, the current in the primary coil of the transformer is 32 A.