Efficiency (AQA GCSE Physics): Quizzes
📚Quizzes
Practise the questions
10 questions from this quiz
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Practise the questions
10 questions from this quiz
What is efficiency?
What is efficiency?
Ratio of useful output to total input
Which formula correctly represents efficiency?
Which formula correctly represents efficiency?
A motor uses J of energy and outputs J of useful work. What is its efficiency?
A motor uses J of energy and outputs J of useful work. What is its efficiency?
30%
How can the efficiency of a system be increased?
How can the efficiency of a system be increased?
By reducing waste output
Which method helps reduce waste output?
Which method helps reduce waste output?
Lubrication
A device has W power input and W useful power output. What is its efficiency?
A device has W power input and W useful power output. What is its efficiency?
75%
What is an example of recycling waste output?
What is an example of recycling waste output?
Absorbing thermal waste as input energy
Thermal insulation helps increase efficiency by:
Thermal insulation helps increase efficiency by:
Reducing waste output
A heater uses J and provides J of useful heat. What is its efficiency?
A heater uses J and provides J of useful heat. What is its efficiency?
90%
Efficiency is often expressed as a:
Efficiency is often expressed as a:
Percentage