The figure shows a girl pulling 5 balloons in her hand for 12m with a force of 1N at an angle of `60^@` below horizontal. How much work does the girl do on the balloons?
A
`-10J`
B
6 J
C
`-6J`
D
12J
Text Solution
Verified by Experts
The correct Answer is:
B
work done is `Fcos theta xx` S here f =1N, angle is `60^@` so cos `theta` = cos 60 = 1/2 and S is 12m substitute and calculate.
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