Efficiency Explained | GCSE Physics Calculations
Efficiency measures how much input energy is transferred into useful output energy.
Can you identify which energy is "wasted"?
What is Efficiency Explained | Calculations?
"The ratio of useful output energy to total input energy."
What is the maximum possible value for efficiency?
A bulb takes 100 J of energy. 20 J is light, the rest is heat. What is its efficiency?
Why can efficiency never be 100% in a mechanical system?
Efficiency Rules
Efficiency = useful output / total input.
Efficiency can be a decimal or a percentage.
It can NEVER be greater than 1 (or 100%).
Misconception: In calculations, students often divide the smaller number by the larger one without checking they are both energy values.
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