Transformers Quiz
Studying this course? Keep your progress in one place.
Pick an answer for each. Quizzes never use energy.
5 questions, one answer each
Each answer is checked as you go, with why.
See all 5 questions
1. Which of the following best describes the main function of the iron core in a transformer?
- A. To increase the magnetic flux linkage between the primary and secondary coils
- B. To reduce the resistance of the copper wire in the coils
- C. To prevent electrical current from flowing between the coils
- D. To store electrical energy during the transformation process
2. A step-up transformer has 200 turns on the primary coil and 1000 turns on the secondary coil. If the primary voltage is 20 V, what is the secondary voltage?
- A. 4 V
- B. 100 V
- C. 50 V
- D. 200 V
3. In an ideal transformer, the primary coil carries 5 A at 230 V. If the secondary coil has half the number of turns as the primary coil, what is the secondary current?
- A. 2.5 A
- B. 5 A
- C. 10 A
- D. 20 A
4. Transformers are used in the National Grid to step up voltage at power stations and step down voltage at homes. Why is stepping up the voltage in the grid essential for efficient power transmission?
- A. High voltage reduces the current, which minimises energy loss as heat in the cables
- B. High voltage makes the cables superconducting, eliminating all resistance
- C. High voltage allows transformers to store more electrical energy
- D. High voltage is required to prevent the alternating current from reversing direction
5. A transformer has 500 turns on its primary coil and 100 turns on its secondary coil. The primary coil carries 2 A and is connected to a 1000 V supply. Calculate the power output from the secondary coil in an ideal transformer.
- A. 200 W
- B. 2000 W
- C. 10000 W
- D. 4000 W