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CBSE Class 9 Answered

a block of mass 5 kg is  allowed to fall from certain height. Find the work done by gravity in one second after the block is dropped  
Asked by prachiverma302003 | 08 Dec, 2018, 08:38: PM
answered-by-expert Expert Answer
Workdone = Force × distance
 
Force = mass × acceleration = 5×9.8 = 49 N
 
distance travelled in one sec = (1/2)×g×t2 = (1/2)×9.8×1×1 = 4.9 m
 
hence workdone = 49×4.9 = 240.1 J
Answered by Thiyagarajan K | 08 Dec, 2018, 09:02: PM

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CBSE 9 - Physics
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