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Question
Sumit does 600 J of work in 10 min and Amit does 300 J of work in 20 min. Calculate the ratio of the powers delivered by them.
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Solution
Sumit: Work done, w1 = 600 J
Time taken, t1 = 10 min = 600 sec
Power, p1 = `w_1/t_1`
= `600/600`
= 1 W
Amit: Work done, w2 = 300 J
Time taken, t2 = 20 min = 1200 sec
Power, p2 = `w_2/t_2`
= `300/1200`
= `1/4`
= 0.25 W
∴ Ratio of Powers = `p_1/p_2`
= `1/(1/4)`
= 4 : 1
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