A child on a skateboard is moving at a speed of 2 m/s. After a force acts on the child, her speed is 3 m/s. What can you say about the work done by the external force on the child?
positive work was done
negative work was done
Zero work was done
Infinite work was done

Academic Physics NCERT Class 9

Here, after applying force speed increases. Therefore, work done is positive.

Therefore, option a). is correct.

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Updated on: 10-Oct-2022

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