Physics 9702 · AS & A Level · Energy conservation

Energy conservation — practice question

Which statement about energy is incorrect?

  • AEnergy is never lost but it may be transferred between different forms.
  • BIn an inelastic collision, the total energy is constant.
  • CThe efficiency of a system is the ratio of the useful energy output to the total energy input.
  • DWhen a machine does work, friction reduces the total energy.

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