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CBSE Class 9 Answered

It takes 20s for a person A to climb up stairs while the other person B does the same in 15s. compare the (1) work done (2)power developed by person A and B
Asked by Muruga | 19 Feb, 2018, 20:23: PM
answered-by-expert Expert Answer
Let h be the height of staircase climbed by A and B. Let mA is weight of A and mB is weight of B.
 
Workdone by A to climb the Staircase, WA = mA×g×h Joules
Workdone by B to climb the Staircase WB = mB×g×h Joules
 
Hence the ratio WA/WB = mA / mB
 
Power developed by A,  PA = (mA×g×h)/20 watts
Power developed by B,  PB = (mB×g×h)/15 watts
 
Power ratio PA/PB = (15mA)/(20mB) = (3mA)/(4mB)


Answered by Thiyagarajan K | 20 Feb, 2018, 07:51: AM

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