µ GCSE | Efficiency

10 quick questions - for GCSE or iGCSE

 

10 minutes maximum! (can you do it in 5?)

 

1. Which of these is used to calculate the efficiency of an energy transfer or shift?

 

Q2-4. This diagram shows the energy transfer as a skateboarder rolls downhill:

 2. What is the percentage efficiency of this transfer of energy?

  • A. 600 %
  • B. 70%
  • C. 30 %
  • D. 1400 %

3. What form of energy is the wasted energy 'X' likely to be?

  • A. Elastic energy stored in the skateboard.
  • B. Chemical energy in the muscles.
  • C. Wind energy from movement.
  • D. Thermal energy from friction.


4. The energy in 'X' can be given as a value or as a percentage. Which of these is correct?

Energy in X (J) Energy in X (%)
A
600 30
B
1400 70
C
30 600
D
70 1400

 

5-7. This diagram shows the efiiciency of a solar panel:

5. What does the 'W' stand for in the diagram?

  • A. Work Done
  • B. Weight
  • C. Wasted energy
  • D. Watts

6. What is the power input to the panel?

  • A. 40 W
  • B. 80 W
  • C. 120 W
  • D. 160 W

7. What is the percentage efficiency of this transfer of energy?

  • A. 75 %
  • B. 67 %
  • C. 33 %
  • D. 25 %

8. "Energy can be transferred usefully, stored or dissipated, but cannot be created or destroyed."

This is called the law of..

  • A. transfer of energy.
  • B. creation of energy.
  • C. conversion of energy.
  • D. conservation of energy.

 

9&10. A large wave power generator is sold with the following specifications:

Peak Power Output: 0.2 kW

Efficiency : 20%

9. 0.2 kW is the same as...

  • A. 0.0002 W
  • B. 20 W
  • C. 200 W
  • D. 2000 W

 

 

10. The maximum power input to the generator is:

  • A. 1 kW
  • B. 4 kW
  • C. 0.01 kW
  • D. 0.04 kW