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8 Energy – forces doing work

A student tests three electric motors, A, B and C.

The Table shows the energy transferred by each motor and the time taken.

Table

Motor	Energy transferred in $J\text{J}$	Time taken in $s\text{s}$
A	6000	20
B	4500	10
C	9000	40

Calculate the power of motor A.

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The student says:

'Motor C is the most powerful because it transfers the most energy.'

Explain why the student is wrong.

[2]

Calculate the time it would take motor B to transfer 9000 J of energy.

[2]

8 Energy – forces doing work Questions