Hi, Ive been trying to complete this question for almost an hour, i was hoping you could provide some advice(adsbygoogle = window.adsbygoogle || []).push({});

At a certain instant, a particle-like object is acted on by a force F = (5.0 N) i hat - (1.0 N) j hat + (10.0 N) k hat while the object's velocity is v = - (2.0 m/s) i hat + (4.0 m/s) k hat. 1)What is the instantaneous rate at which the force does work on the object?

2)At some other time, the velocity consists of only a j component. If the force is unchanged, and the instantaneous power is -12 W, what is the velocity of the object just then?

I tried taking the dot product of the force and velocity, making sure i only multiplied the like terms of the unit vectors. then i took the hypotenuse using pythagoras, but the answer i get is 41.2 Watts and its not right? please could someone help?

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# Homework Help: Power particle-like object problem

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