8 Energy – forces doing work

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Question 92

H

A machine has an input power of 800 W and a useful power output of 600 W. It is modified so that the wasted power is halved while the useful power is unchanged. What is the new efficiency, to two significant figures?

[1]

$86%86\%$

$38%38\%$

$88%88\%$

$75%75\%$

8 Energy – forces doing work

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Question 92

H

A machine has an input power of 800 W and a useful power output of 600 W. It is modified so that the wasted power is halved while the useful power is unchanged. What is the new efficiency, to two significant figures?

[1]

$86%86\%$

$38%38\%$

$88%88\%$

$75%75\%$

8 Energy – forces doing work

Question 92

Markscheme

8 Energy – forces doing work

Question 92

Markscheme

8 Energy – forces doing work

Question 92

8 Energy – forces doing work Questions

8 Energy – forces doing work

Question 92

8 Energy – forces doing work Questions