Potential difference between two plates Please help

AI Thread Summary
To determine the potential difference between two charged plates that causes a charged sphere to hang at a 30-degree angle, one must analyze the forces acting on the sphere, including electric field, gravity, and tension. The equilibrium condition requires resolving these forces into their x and y components and setting the net forces in each direction to zero. The relevant equations involve calculating the electric field created by the plates and relating it to the potential difference. A free body diagram can aid in visualizing the forces and their components. This approach will lead to the necessary calculations for the potential difference required to achieve the specified angle.
sully677
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A small sphere with mass 2.10 g hangs by a thread between two large parallel vertical plates 5.00 cm apart . The plates are insulating and have uniform surface charge densities + sigma and - sigma . The charge on the sphere is q = 7.70×10−6 C

What potential difference between the plates will cause the thread to assume an angle of 30.0 degrees with the vertical?
 
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Sounds like a homework question...

What have you tried?
 
Trying the potential difference equations, but the angle is messing my calculations up
 
sully677 said:
bump

In the equilibrium position, what are the forces acting on the charged sphere?
 
The electric field, gravity and the tension of the string?

What formula would I need?
 
sully677 said:
The electric field, gravity and the tension of the string?

What formula would I need?
Draw the free body diagram with these forces. Resolve them into x and y components. For equilibrium equate net X-component and net y-component equal to zero.
 

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