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Question
A lamp consumes 1000 J of electrical energy in 10 s. What is its power?
Solution
Power = `"Energy consumed (or work done)"/"Time taken"`
W = 1000 J, t = 10 s
i.e., P = `W/t`
= `(1000 J)/(10 s)`
= 100 J/s
i.e., P = 100 W
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