Force on 3uC Charge - Solving Coloumb's Law Problem

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Homework Statement


Find force on 3uC charge.
Diagram of three point charges forming an isosceles triangle: +2uC at the top-left and bottom-left corners, +3uC at the right apex. The vertical left side is labelled 3 cm, the horizontal median from the left side to the apex is labelled 4 cm.


Homework Equations


Coulomb's law equation: magnitude of F equals k_e times the absolute value of q1 q2 divided by r squared.


The Attempt at a Solution


Assuming the 3uC charge is at point A and others are at point B and C

FA = FAB + FAC
FAB = K*(2*3)/5
FAC = K*(2*3)/5

 
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Ember Cult said:

Homework Statement


Find force on 3uC charge.
Diagram of three point charges forming an isosceles triangle: +2uC at the top-left and bottom-left corners, +3uC at the right vertex. Left side labelled 3 cm, horizontal base-to-vertex distance 4 cm.


Homework Equations


Coulomb's law for force magnitude: |F| = k_e |q1 q2| / r^2, with k_e as the Coulomb constant, q1 and q2 as charges, and r as separation distance.


The Attempt at a Solution


Assuming the 3uC charge is at point A and others are at point B and C

FA = FAB + FAC
FAB = K*(2*3)/5
FAC = K*(2*3)/5

Remember, force is vector. The two forces exerted on the 3uC charge have different directions. Add them by their horizontal and vertical components.
The magnitude of the Coulomb force is inversely proportional to the square of the distance. Correct your formulas.
 
ehild said:
Remember, force is vector. The two forces exerted on the 3uC charge have different directions. Add them by their horizontal and vertical components.
The magnitude of the Coulomb force is inversely proportional to the square of the distance. Correct your formulas.
Your relevant equation should include unit vector of r. Calculating 2 charge particles is not a problem but not in 3D or many particles in 2D.