Question

An electric heater of power 3 kW is used for 10 h. How much energy does it consume? Express your answer in (i) kWh (ii) joule.

April 8, 2024

Answer

Power of the electric heater = 3kW

Time for which the electric heater is used = 10 hours

We know,

Energy consumed = power × time

(i) Energy consumed in kWh = 3 kW × 10 h = 30 kWh

(ii) Energy consumed in joule

= 30 kWh

= 30 × 3.6 × 10⁶

= 1.08 × 10⁸ J

💡 Some Related Questions

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(b) What is the total mechanical energy at point C?
(c) What is the speed of the bob at position A when released from position B ? (Take g = 10 ms^-2)

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