Find Mag of Charges for 50 cm, 0.2g & 37 Degrees

AI Thread Summary
To find the magnitude of charges for two balls suspended by a 50 cm string at a 37-degree angle, the forces acting on the balls must be analyzed, including gravitational, tension, and electromagnetic repulsion. The horizontal component of the forces indicates that the balls are pushed apart due to electromagnetic forces, which must be calculated to determine the charge. The distance between the charges is crucial, with half the distance being 15.9 cm. The final calculated charge is approximately 5.57 x 10^-15 C, which was confirmed by multiple participants in the discussion. Understanding the relevant equations for force between point charges is essential for solving this problem.
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Homework Statement


I need to find the magbitude of charges

Lenght of string - 50 cm
mass of balls - 0.2 grams
theeta - 37 degrees

Homework Equations



K-8.99x10^9 [/B]

The Attempt at a Solution



I found that half the distance between the balls is 15.9 cm but i don't know how to continue[/B]
 

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pawlist said:

Homework Statement


I need to find the magbitude of charges

Lenght of string - 50 cm
mass of balls - 0.2 grams
theeta - 37 degrees

Homework Equations



K-8.99x10^9 [/B]

The Attempt at a Solution



I found that half the distance between the balls is 15.9 cm but i don't know how to continue[/B]

Okay, first, the balls will try to move toward one another because of the combined force of gravity and tension of the string, you should calculate the force vectors on the balls and figure out the horizontal component of the forces that drives the balls to move toward one another. This force, however, failed to move the balls because an equal and opposite force is acting on each ball that is pushing them away, and this force is the electromagnetic repulsion. You find the magnitude of that force and use the equation (I don't which one but you should have learned it) to calculate the charge based on distance between charges and the amount of repulsion. Ask for clarification iyou want.
 
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These are all of the available equations but i don't know which one to use.I uploaded an image
 

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pawlist said:
These are all of the available equations but i don't know which one to use.I uploaded an image
force between point charge. You know the force and the distance, the charges should be a piece of cake to find.
 
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My final answer is 5.57^-15 can you confirm please?
 
pawlist said:
My final answer is 5.57^-15 can you confirm please?
That is what I got too, but worship no authority!
 
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