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A porter lifts a heavy suitcase of mass ...

A porter lifts a heavy suitcase of mass 80 kg and at the destination lowers it down by a distance of 80 cm with a constant velocity . Calculate the workdone by the porter in lowering the suitcase
(take `g = 9.8 ms^(-2)` )

A

`-62720.0` J

B

`+627.2` J

C

`-627.2`J

D

784.0J

Text Solution

Verified by Experts

The correct Answer is:
C

`F_("Person")= mg= 784N`
`W_("person")= F_(P) S cos 180^(@)= -784 xx 80 xx 10^(-2)= -627.2J`
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