How Much Charge Do Repelling Styrofoam Balls Carry?

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The discussion revolves around calculating the charge carried by three identical Styrofoam balls suspended in equilibrium, forming an equilateral triangle. The user initially determined the repulsive electric force acting on one ball to be 6.138e-3 N using tension and weight components. They applied Coulomb's law but arrived at a charge value of q = 1.88e-7 C, which they suspected was incorrect. After receiving assistance, the user confirmed they solved the problem and requested the thread to be closed. The conversation highlights the application of physics principles to solve electrostatic problems.
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Homework Statement


Three identical small Styrofoam balls (m = 1.84 g) are suspended from a fixed point by three nonconducting threads, each with a length of 46.5 cm and with negligible mass. At equilibrium the three balls form an equilateral triangle with sides of 30.0 cm. What is the common charge q carried by each ball?

Homework Equations


Coloumb's law

The Attempt at a Solution


I've figured out that the repulsive electric force acting on one ball is 6.138e-3 N.
This was done by figuring out the x-component of tension by using the weight.
After that, using coloumb's law, i got that
F = (9.99e10)(q2)
i then figured that the net force would equal F + F.
I added the two force vectors using the cosine law and splitting it into components and i arrive at
q = 1.88e-7 C
however, this seems to be wrong.

Can anyone help please?
 
Last edited:
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I solved it!
Could a moderator please close this thread?
Thanks.
 
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