5. An electrical power plant generates electricity with a current of 50 A and a potential difference of 20 000 V. In order to minimize the power losses due to the high current heating up the line, a transformer steps up the potential difference to 500 000 V before it is transmitted. What is the current in the transmission lines?

2A

Explanation:

A transformer operates on the principle of mutual inductance. That is, the flow of induced current or voltage in a coil due to an alternating or carrying current in a neighboring coil. For a transformer, we can write;

Es/Ep = Ip/Is

Where;

Es= voltage in the secondary coil= 500,000V

Ep= voltage in the primary coil = 20,000 V

Is= current in the secondary coil = ???

Ip= current in the primary coil = 50A

Thus;

Es×Is= Ep×Ip

Is= Ep × Ip/Es

Is= 20000 × 50/500000

Is= 2A