A transformer supplies 60 watts of power to a device that is rated at 20 volts (rms). The primary coil is connected to a 120-volt (rms) ac source. What is the current I1 in the primary coil?

I = 0.5A

Explanation:

Hello,

Assuming the transformer is an ideal transformer, we can calculate the value of the current using the formula.

Data;

Power = 60 watt

Primary voltage = 120 volts (rms)

Power (P) = current (I) * voltage (V)

P = IV

This formula is the relationship between power, current and voltage.

Current = power / voltage

I = P / V

I = 60 / 120

I = 0.5A

The current in the primary coil is 0.5A