Electrostatic equilibrium, deflection of a cobweb

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SUMMARY

The discussion centers on solving for the distance between charges in an electrostatic equilibrium scenario involving a cobweb. The equation derived is tan θ = (k q²) / (m g r²), where k is Coulomb's constant, q is charge, m is mass, g is gravitational acceleration, and r is the distance between charges. Participants emphasize the need to establish a relationship between r and θ using geometric principles, particularly given the provided dimension of 0.35m. The consensus is that additional geometric equations are necessary to solve for the unknowns.

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marcusesses
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Homework Statement



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Homework Equations



After creating a FBD and analyzing the forces, I get the equation for the angle as

## tan \theta = \frac{k q^2}{m g r^2} ##

The Attempt at a Solution


[/B]
I have tried to find a way to find the distance between the charges ## r ##, but the only way I can think of to find it required the angle. I do not know how the question can be solved without knowing at least one of the two variables, and my first inclination is just to assume there is not enough information.

Any help would be appreciated! Thanks!
 
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I think you can write another equation for r in terms of theta using the geometry alone..

Hint: You are given the dimension 0.35m
 
marcusesses said:
I have tried to find a way to find the distance between the charges r r , but the only way I can think of to find it required the angle.
Find the relationship between r and ##\theta##.

(CWatters beat me to it while I was snoozing!)
 

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