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A 45 kg box starts from rest and moves o...

A 45 kg box starts from rest and moves on a smooth plane the force that varies with time as shown. The velocity of the box at t=8 sec is:

A

`6 m//s`

B

`8 m//s`

C

`12 m//s`

D

`24m//s`

Text Solution

Verified by Experts

The correct Answer is:
D
`intF dt=M(v-u)="area"`
`M(v-u)=1/2xx4^(2)xx180=360`
`v=360/45=8m//sec`
Velocity at 8 second
`v_(f)=v+at=8+4xx4=24m//sec`
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