Free to use. Edit it, share it and hand it out to your students.
Oak National Academy
12 questions
Match the following terms, which are related to transformers, to the correct definitions.
Which of the following is a definition of the efficiency of a device?
Which of the following is the frequency of mains electricity?
Match each of the following to the typical voltage(s) it supplies or requires.
Which of the following induce a potential difference across the ends of a coil of wire?
A transformer with 100% efficiency changes the voltage from 1000 V to 33 kV. If the current through the secondary coil is 20 A, the current through the primary coil is ___ A.
When is a p.d. (potential difference) induced across the secondary coil of a transformer?
Which of the following can a transformer increase?
How does the number of turns on the coils affect the potential difference in a transformer?
Calculate the output p.d. of a transformer if the primary p.d. is 240 V, the primary coil has 50 turns, and the secondary coil has 25 turns.
If the power input to a transformer is 1000 W and the power output is 950 W, what is the efficiency of the transformer?
What current is drawn from a 230 V power supply to a transformer if the output is 15.0 V and 1000 mA? Give your answer in mA to 3 s.f.
