Physics 9702 · AS & A Level · Energy conservation

Energy conservation — practice question

In many filament lamps, up to $92\,\text{J}$ of energy is released as thermal energy for each $8\,\text{J}$ of energy released as light. What is the efficiency of a filament lamp, given as the percentage of electrical energy converted into light energy?

  • A8%
  • B9%
  • C91%
  • D92%

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