ALTERNATING CURRENT AND DIRECT CURRENT
2 marks · EasyA small electric pump transfers 4800 J of energy in 4 minutes. Calculate the power of the pump.
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20 W (±1)
Also accept: 20 watts; 20
Common mistakes: Not converting minutes to seconds
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Marking points
M1 · 1 mark · Converts 4 minutes to 240 seconds and recalls P = E / t.
A1 · 1 mark · Divides 4800 J by 240 s to get 20 W.
Worked solution
Convert 4 minutes to seconds: 4 × 60 = 240 s.