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A kettle transfers 2200 W of power. How much energy does it transfer in 120 seconds? Also can I have your working out please ;)

Respuesta :

that power is measured in kilowatts here instead of the more usual watts. To convert from W to kW you must divide by 1,000.

For example, 2,000 W = 2,000 ÷ 1,000 = 2 kW.

Also note that time is measured in hours here, instead of the more usual seconds. To convert from seconds to hours you must divide by 3,600.

For example, 7,200 s = 7,200 ÷ 3,600 = 2 h.

Example calculation

A 2 kW electrical fire is switched on for 3 hours. It uses 2 × 3 = 6 kWh of electrical energy.

Joules, watts and seconds

You also use the equation E = P × t when:

E is the energy transferred in joules, JP is the power in watts, WT is the time in seconds, s.

For example, a 20 W lamp lit for 100 seconds transfers 20 × 100 = 2,000 J (2 kJ).

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