(adsbygoogle = window.adsbygoogle || []).push({}); 1.A small 3.94 g plastic ball is suspended by a

27.9 cm long string in a uniform electric field

of 3400 N/C.

The acceleration of gravity is 9.8 m/s2 , and

the Coulomb constant is 8.99×109 N · m2/C2.

If the ball is in equilibrium when the string

makes a 43.2◦ angle with the vertical as in-

dicated, what is the net charge on the ball?

Answer in units of μC.

2. E=F/q

Fe=kq/r^2

3. Well I'm kind of lost. When they ask for the net charge, I just plugged the F, found using F=mg, and electric field into the equation E=F/q. And then I used that q and plugged it into the Fe=kq/r^2 equation, and found q. I thought that was the answer, but apparently not. I don't understand how to do the problem at ALL. please help. thanks in advance.

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# Homework Help: What is the net charge of the ball?

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