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    Jack carries a 20kg suitcase up a set of stairs in 5s
    Jill caries a 12 kg suitcase up the same set in 3 s.
    Find the relationship between the power exerted by Jack and Jill?
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    (Original post by jsmith6131)
    Jack carries a 20kg suitcase up a set of stairs in 5s
    Jill caries a 12 kg suitcase up the same set in 3 s.
    Find the relationship between the power exerted by Jack and Jill?
    Power is Work/Time. Time is given. What work is done by each person?
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    (Original post by jsmith6131)
    Jack carries a 20kg suitcase up a set of stairs in 5s
    Jill caries a 12 kg suitcase up the same set in 3 s.
    Find the relationship between the power exerted by Jack and Jill?
    Power exerted by both of them is same.

    Work done = Increase in potential Energy (PE)
    Let height of staircase be (h), and let g be (10)
    Increase in PE = mgh
    Increase in PE of Jack = 20 x 10 x h
    Increase in PE of Jill = 12 x 10 x h

    Power = Work Done/Time

    Power by Jack = \frac{200h}{5}
    Power by Jill= \frac{120h}{3}

    Power exerted by both of them is 40h.
 
 
 
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