Transformers Practice
1. The transformer in the diagram below has a primary coil consisting of 200 turns and a secondary coil
consisting of 4000 turns. The primary coil is supplied with an input AC voltage of 120 V.
a. Is this a step up or step down transformer?
b. What is the output voltage in the secondary circuit?
c. The current in the secondary circuit is 2.0 A. What is the current in the primary circuit?
d. What is the power of the transformer?
2. The transformer in the diagram below is similar to those found in laptop computers. The power supply
in a certain laptop computer requires a secondary voltage of 6.0 V from a 120 V primary line.
a. Is this a step up or step down transformer?
b. If the primary coil has 450 turns, how many does the secondary coil have?
c. A 0.150 A current is in the computer. What is the current in the primary circuit?
d. What is the power of the transformer?