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A body of mass 2kg starts from rest and ...

A body of mass `2kg` starts from rest and moves with uniform acceleration. It acquires a velocity `20ms^-1` in `4s`.
The power exerted on the body at `2s` is

A

(a) `50W`

B

(b) `100W`

C

(c) `150W`

D

(d) `200W`

Text Solution

Verified by Experts

The correct Answer is:
B
`v=u+atimplies20=0+axx4impliesa=5ms^-2`
`F=ma=2xx5=10N`
Velocity at `2s: v_1=at=5xx2=10ms^-1`
`Power=Fv_1=10xx10=100W`
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