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3 Conservation of energy

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Question 106
H

A machine receives 1000 J and transfers 500 J usefully per operation.

A redesign reduces the energy dissipated by air resistance by 80 J, but increases the energy dissipated by friction by 30 J. All other unwanted transfers and the input energy are unchanged.

What is the efficiency after the redesign?

[1]
A

45%45\%45%

B

55%55\%55%

C

58%58\%58%

D

61%61\%61%

Markscheme

3 Conservation of energy Questions

  1. GCSE
  2. /Physics
  3. /3 Conservation of energy

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