A lamp consumes 1000 J of electrical energy in 10 s. What is its power?

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Chapter 9

NCERT

Class 9

Science

Solutions

3. A lamp consumes 1000 J of electrical energy in 10 s. What is its power?

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Question:

A lamp consumes 1000 J of electrical energy in 10 s. What is its power?

Answer:

We can obtain the average power by dividing the total energy used by the total time taken.

So, Average power = Total energy used/ Total time taken

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Note: The term average power is used when the power of agent (such as an instrument or device) changes over time. That is, if works at different rates in different time intervals.

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