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What is the amount of work done by a boy...

What is the amount of work done by a boy when
(i) he holds a bundle of books of mass 2 kg for 5 minute?
(ii) be lifts up the same bundle of books through 1 metre to keep it on his study table?

A

0,4.9J

B

0,19.6J

C

19.6J,0

D

0,9.8

Text Solution

Verified by Experts

The correct Answer is:
B
`W =vec( F ) . vec( s) = Fs cos theta `
`25 = 10 xx 5 xx cos theta `
`:. cos theta = ( 25)/( 50) = (1)/(2)` `:. theta = 60^(@)`
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