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A force vec F = (3t hat i + 5 hat j)N ac...

A force `vec F = (3t hat i + 5 hat j)N` acts on a body due to which its position varies as `vec S =(2t^2 hat i - 5 hat j)`. Work done by this force in initial 2s is:

A

23 J

B

32 J

C

zero

D

can't be obtained

Text Solution

Verified by Experts

The correct Answer is:
B
`W=intvec(F).dvec(s)=int(3hati+5hatj).(4t dt hati) =int_(0)^(2) 12 t^(2) dt =(12[t^(3)]_(0)^(2))/3=32 J`
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