Hi all, can some one please help me on this problem;(adsbygoogle = window.adsbygoogle || []).push({});

The acceleration of a marble in a certain fluid is proportional to the speed of the marbles, and is given (in SI units) by a= -3.00V^2 for v>0. If it enters this fluid with a speed of 1.50 m/s, how long will it take for the marble to reach half its intial speed.

I have released that

Vf=Vi + a(t)

.75=1.5+ a(t)

-.15=a(t)

and that A=(Vf-VI)/t

I am stuck after this. Please help me.

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# Homework Help: Tricky kinematic problem.

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