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A force vec(F) = (40 hat (i) + 10 hat(...

A force ` vec(F) = (40 hat (i) + 10 hat(j))` N acts on body of mass 5 kg. If the body starts from rest, its position vector `vec(r)` at time t = 10 s, will be

A

`(100 hati + 400 hatj)m`

B

`(400 hati + 100 hatj)m`

C

`(100 hati +100 hatj)m`

D

`(400 hati + 400 hatj)m`

Text Solution

Verified by Experts

The correct Answer is:
B
`(dvecv)/(dt) = veca = vecF/m(8hati + 2hatj)m//s^(2)`
`vecr=(8hati + 2hatj) t^(2)/2 m`
At t = 10 sec.
`vecr =[(8hati +2hatj)50]m`
`rArr vecr = (400 hati + 100 hatj) m`
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