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CBSE Class 9 Answered

two children A and B both weighing 40kg climbs a rope of height 8cm.A takes 15s and B takes 20s to reach the height calculate the amount of work done by both A and B?
Asked by Anandakrishnan . | 04 Mar, 2011, 12:00: AM
answered-by-expert Expert Answer
Dear student,
 
Work done = FxD
 
F= mass X acceleration= 40X10(take g =10)= 400
 
Work done = 400 X 8
 
Work done = 400X8
 
As there is no net displacement, though energy is spent, the work done does not depend on time.
 

this eg will make it clear

consider a person pushing a wall for a whole day,though he has been expending his energy,the work done by him is zero.

as no displacement is caused.

i hope it is clear

Team
Topperlearning.com
Answered by | 07 Mar, 2011, 01:56: PM

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