An electric heater is rated 1500 W. How much energy does it use in 10 hours?

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Chapter 10 NCERT Class 9 Science SOLUTIONS

14. An electric heater is rated 1500 W. How much energy does it use in 10 hours?

Question:

An electric heater is rated 1500 W. How much energy does it use in 10 hours?

Answer:

Power of electric heater

P = 1500W

Time, t = 10 hour

The energy used = Power × time

= 1500W × 10h

= 15000Wh

= 15 Wh

= 15 unit [∵ 1 kWh = 1 unit]

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