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At time t = Os a particle starts moving ...

At time t = Os a particle starts moving along the x-direction. If its kinetic energy increases uniformly with time Y', the net force acting on it must be proportional to :

A

constant

B

t'

C

`(1)/(sqrt(t))`

D

`sqrt(t)`

Text Solution

Verified by Experts

The correct Answer is:
c
As `K.E. prop t`,then
`1/2mv^2 prop t` or `1/2mv^2=kt`, where .k. is a constant.
If p = mv is the linear momentum of the body,then `(p^2)/(2m)=kt` or `p=sqrt(2mk)xxt^(1/2)`or `F=(dp)/(dt)=sqrt(2mk)xx1/2xxt^(1/2)` or `F prop (1)/(sqrtt)`.
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