1. The problem statement, all variables and given/known data(adsbygoogle = window.adsbygoogle || []).push({});

In a laboratory, a particle of charge -6C is held stationary because it is placed in an electric field E=(0,0,-15)N/C which suspends it against gravity. What is the mass of the particle? Give answer in kg.

2. Relevant equations

I THINK

E= F/q

F= ma or F= G m1 m2 / r^2

3. The attempt at a solution

Ok, so I haven't actually had a chance to attempt this yet because A) I don't understand the notation of E in this equation, so I don't know if it is acceptable to just use -15 for E, and B) if I even have the right equations to use, I don't know what the acceleration is or how to use the second equation. Please help

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# Homework Help: Help with Electric Fields

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