Coulomb's Law (Finding magnitude & direction of net force)

AI Thread Summary
The discussion revolves around calculating the net force on three positive particles, each with a charge of +11.5 µC, positioned at the corners of an equilateral triangle with a side length of 13.0 cm. The user attempts to find the net force on one particle by analyzing the forces exerted by the other two particles, utilizing symmetry to simplify the calculations. They express confusion over their calculated result of 0.0122, which they believe is incorrect, and seek clarification on their method. A suggestion is made to double-check the units used for distance in their calculations. The conversation emphasizes the importance of accurate unit conversion and symmetry in solving electrostatic force problems.
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Homework Statement



Three positive particles of equal charge, +11.5 µC, are located at the corners of an equilateral triangle of side d = 13.0 cm (Fig. 16-50).

Calculate the magnitude and direction of the net force on each particle.

Image is here: http://www.webassign.net/giancoli5/16-38alt.gif


Homework Equations



k*|q1||q2| / r2



The Attempt at a Solution



Solving for net force on Q1:
Ok, I drew a free body diagram. The force from q2 goes up and to right, q3 goes up and to left. I thought that since the x values will be the same due to symmetry, I could cancel them out and solve for the y value.

So, I can find one force and multiply by two since they will be the same.

I did 2 * { (9e9 * 11.5e-6 * 11.5e-6)/132 } * sin60

I multiplied by sin60 to get the y value.

My answer is coming out to be .0122, which is wrong. I'm not sure what I'm doing wrong. Can someone please explain? Thanks!
 
Physics news on Phys.org
Check your units for d! :)
 

Thread 'Errors and significant figures'

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Thread 'A cylinder connected to a hanging mass'

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