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A girl is carrying a school bag of 3 kg ...

A girl is carrying a school bag of 3 kg mass on her back and moves 200 m on a lavelled road. The wrok done against the gracitational force will be `(g=10ms^(2))`

A

`6xx10^(3)J`

B

`6J`

C

`0.6J`

D

zero

Text Solution

Verified by Experts

The correct Answer is:
D
We know that, work done `=F.dcostheta`
Force on school bag makes an angle `90^(@)` from the road.
i.e., `theta=90^(@)`
`W=F.dcos90^(@)" "(":'cos90^(@)=0^(@))`
W = 0

Hence, work done against the gravitational force is zero.
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