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A boy is moving on a straight road again...

A boy is moving on a straight road against a frictional force of 5 N. After travelling 1.5 km, he forgot the path at cross roads of radius 100m. He moves on the circular path for one and half cycle and then he moves forward up to 2 km. Calculate the work done by him.

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The correct Answer is:
The work done by the boy is 18500 J.
`F=5N`
Displacement on the circular path :
1 cycle = 0 and half cycle = `2r=2xx100`
`=200m`
Total displacement = `1.5km+200m+2km`
`=3700m`
Work done by the boy = `Fxxs`
`=5Nxx3700m`
`=18500J`
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