Here's the problem:(adsbygoogle = window.adsbygoogle || []).push({});

Two particles each have a mass of 6.6x10^-3 kg. One has a charge of +5.0x10^-6 C, and the other has a charge of -5.0x10^-6 C. They are initially held at rest at a distance of 0.70 m apart. Both are then released and accelerate toward each other. How fast is each particle moving when the separation between them is one-half its initial value?

I've tried a couple of different ways to attack this, with this one making the most sense to 'me' :rofl: :

Knowing both charges and the distance between them, I applied Coulomb's Law to determine a force of .459 (maybe this is my problem? One charge has to remain stationary..?)

I then applied this to Newton's F=ma, which would yield an acceleration of 69.49 m/s/s. I finally applied this to Kinematics and found the final velocity after 0.175m (the distance each particle traveled after a combined 0.30 m change in distance).

So...where'd it all go wrong? I doubt I'm attacking this the right away, so any thoughts are appreciated :)

Thanks.

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# Homework Help: Particle acceleration problem

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