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[Dr.Pure]

The only force acting on a 2 kg body as it moves along a positive x axis has an x component Fx=-6x N with x in meters. The velocity at x=3m is 8 m/s a) what is the velocity of the body at x=4?? b) at what a positive value of x will the body have a velocity of 5 m/s??



A force of 5 N acts on a 15kg body initially at rest. compute a)the work done by the force in the first second
b) the instantaneous power due to the force at the end of the third second??

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