Question

A transformer has 1000 turns in the primary coil and 100 turns in the secondary coil. If the primary coil is connected to a 120 V outlet and draws 0.050 A, what are the voltage and current of the secondary coil

Answer 1

Answer:

The voltage on the secondary is 12 V while the current is 0.5 A.

Explanation:

A transformer works by changing the level of the voltage and current on a circuit using a magnetic field and two coils. The ratio by wich they are changed is dependant on the ratio of turns between the primary and secondary of the transformer. In this case we have a ratio for the voltage of:

ratio = (turns on the secondary)/(turns on the primary)

ratio = 100/1000 = 0.1

So in this case the voltage delivered to the primary will be multiplied by 0.1. We can now calculate the voltage on the secondary:

Voltage secondary = Voltage primary* ratio = 120*0.1 = 12 V

The transformer maintains roughly the same power output on both sides, since the power output on a electric circuit is given by the product of the voltage by the current on that circuit, to maintain the same power when the voltage has been droped the current must be raised by the same ratio. So we have:

Current secondary = Current primary*(1/ratio) =0.05*(1/0.1) = 0.5 A