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A block of mass 1kg start moving with co...

A block of mass 1kg start moving with constant acceleration `a=4m//s_(2)` Find.
(a) average power of the net force in time inteval from `t=0` to `t=2s`,
(b) instantaneous power of the net force at `t=4 s`.

Text Solution

Verified by Experts

The correct Answer is:
A, B, D
(a) `P_(av)=W/t =((1)/(2)mv^(2))/t =((1)/(2)m(at)^(2))/t`
`=1/2ma^(2) t =1/2 xx 1 xx (4)^(2) (2)`
`=16W`
(b) `P_(i) =Fv=(ma)(at)`
`=mg^(2)t=(1) (4)^(2) (4)`
`64W`.
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