<p>I didn't see an official Physics C thread this year, but disregard this thread if I'm wrong.</p>
<p>I'm doing some practice homework problems right now from this testmaker that's supposed to be harder than the AP test. I can't figure out this problem even though it looks stupidly easy.</p>
<p>The acceleration of a particle in the x direction from rest is given by a = 3x. The velocity of the particle when the displacement, x, is x=5 meters is what?</p>
<p>According to the answer key, the answer is 8.66m/s, which makes no sense to me whatsoever. Can someone please explain how to do this? Thanks.</p>