A small 2g plastic ball is suspended by a 20 cm long string in a uniform electric field. If the ball is in equilibrium when the string makes a 15 degree angle with the vertical as indicated, what is the net charge on the ball?
Here's the diagram:
Coulumb's Law of electric force equation. F=kq1q2/r^2
Electric force equations. F=qE
The Attempt at a Solution
First I drew a FBD of the ball and the forces acting on it.
Did I draw it correctly? I just want to confirm this first. There are only 2 x direction forces acting on it correct? The F_e is equal to q*E?? E being the electric force?
So do I just make T_x=qE and solve for the q? I don't get what they mean by net charge on the ball. Thanks! =D
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