Question
The diagram shows a transformer. There are 460 turns on the primary coil and 24 turns on the secondary coil. The primary voltage is 230 V.
What is the secondary voltage?
A 2.0 V
B 12 V
C 48 V
D 4400 V
Answer/Explanation
Ans: B
Question
The diagram shows a transformer connected to a 240 V a.c. supply.
What is the potential difference across the secondary coil of the transformer?
A 30 V
B 120 V
C 240 V
D 480 V
Answer/Explanation
Ans: B
Question
A transformer has 200 turns on its primary coil and is connected to a 240 V a.c. supply.
The output voltage of the transformer is 60 V a.c..
How many turns are on the secondary coil of the transformer?
A 20
B 50
C 72
D 800
Answer/Explanation
Ans: B
Question
An electrical device changes the voltage of an electrical supply from 240 V a.c. to 20 V a.c.
What is this device?
a generator
a relay
a transformer
a voltmeter
Answer/Explanation
Ans: C
Question
The diagram shows a transformer with primary coil P and secondary coil S. The input potential difference across coil P is VP. The output potential difference across coil S is VS. The number of turns in coil P is NP. The number of turns in coil S is NS.
Which equation relates the input and output voltages to the numbers of turns in P and in S?
Answer/Explanation
Ans: A