Calculating Charge of 3 Identical Point Charges

AI Thread Summary
Three identical point charges, each with a mass of 140g and charge +q, are suspended from strings, forming an angle of 48 degrees with the vertical. To determine the charge value q, the distance between the charges must be established, which can be calculated using trigonometric functions. The forces acting on each charge include tension, gravitational force, and electrostatic force, which can be analyzed using Lami's theorem. The discussion emphasizes the necessity of knowing the distance between the charges to solve the problem effectively. This thread highlights the complexities of statics problems involving multiple forces and point charges.
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Three identical point charges, each of mass 140g and charge +q, hang from three strings. If the lengths of the left and right strings are each 10 cm, and each forms an angle of 48 degree with the vertical, determine the value of q.
 
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This is a statics problem. The forces acting on one of the point charges are tension, gravity, and electro-magnetism.

Of course, you can't solve the problem unless it let's you know what the distance between the point charges is.
 
NateTG said:
This is a statics problem. The forces acting on one of the point charges are tension, gravity, and electro-magnetism.

Of course, you can't solve the problem unless it let's you know what the distance between the point charges is.

We do know the distances.. Lsin(theta)
 
use lami's theorm on any of the left and right charge, forces being Tension, mg, electric force
 
Realize that this thread is 7 years old.
 
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