Physics 9702 · AS & A Level · Energy conservation

Energy conservation — practice question

A new kind of filament lamp has been created by researchers and it has an efficiency of $40\%$. The efficiency of older filament lamps is $5.0\%$. Both lamp types give the same useful output power. What is the ratio $\dfrac{\text{input power to new type of lamp}}{\text{input power to old type of lamp}}$?

  • A0.13
  • B0.63
  • C1.6
  • D8.0

Worked solution & mark scheme

This 1-mark question has a full step-by-step worked solution and mark scheme.

  • Full mark scheme, point by point
  • Step-by-step worked solution
  • Write your answer & get it marked instantly by AI