Question 37 of 87 in Units (Electricity)

ALTERNATING CURRENT AND DIRECT CURRENT

2 marks · Easy

A 30 W charger is used for 2 hours.

(a)

Calculate the total energy transferred in joules.

[2 marks]

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(a) 216000 J

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Marking points

M1 (a) · 1 mark · Converts 2 hours to 7200 seconds and recalls E = P × t.

A1 (a) · 1 mark · Calculates 30 × 7200 = 216000 J.

Worked solution

Convert 2 hours to seconds: 2 × 3600 = 7200 s.

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