An ideal transformer has 100 turns in the primary coil and 50 turns in the secondary coil. The primary voltage is 240 V. What is the secondary voltage?
Answer and explanation
Correct answer: C. 120 V
- Step 1: .
- Step 2: V.
Answer
120 V.
Why not the others: 480 V: it steps the voltage up instead of down. 190 V: it adds and subtracts the numbers. 60 V: it divides by twice the turns ratio.
Practise more Electricity and Magnetism.
Free questions with an explanation for every one, and full timed HKDSE (Hong Kong) mock tests.
More Electricity and Magnetism questions
- A current of 0.5 A flows through a 6 Ω resistor. What is the potential difference across it?
- A current of 4 A flows through a 10 Ω resistor. What is the potential difference across it?
- A current of 4 A flows through a 12 Ω resistor. What is the potential difference across it?
- A current of 3 A flows through a 10 Ω resistor. What is the potential difference across it?
- A 4 Ω resistor and a 12 Ω resistor are connected in parallel. What is the total resistance?
- Resistors of 4 Ω, 6 Ω and 4 Ω are connected in series. What is the total resistance?