Calculate the magnitude and direction of the net electric force

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SUMMARY

The discussion focuses on calculating the net electric force acting on three point charges: q1 = 6.60 µC, q2 = 1.41 µC, and q3 = -1.9 µC, with separation distances d1 = 3.00 cm and d2 = 2.00 cm. The correct formula used is F_{e}=k_{e}\frac{|q_{1}||q_{2}|}{r^{2}}, where k_{e} = 8.9876e9 N m²/C². The user initially miscalculated the charge values by converting microcoulombs to nanocoulombs incorrectly, leading to an incorrect net force calculation. After correcting the conversions, the net electric force was determined to be 47.8 N to the left.

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  • Knowledge of unit conversions, specifically microcoulombs to coulombs
  • Familiarity with basic physics concepts of electric charge and force
  • Ability to perform calculations involving scientific notation
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  • Practice unit conversions in physics, particularly for electrical units
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crybllrd
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Homework Statement



Three point charges lie along a straight line as shown in the figure below, where q1 = 6.60 µC, q2 = 1.41 µC, and q3 = -1.9 µC. The separation distances are d1 = 3.00 cm and d2 = 2.00 cm. Calculate the magnitude and direction of the net electric force on each of the charges.

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I need to state the magnitudes and directions of all 3 charges.

Homework Equations



F_{e}=k_{e}\frac{|q_{1}||q_{2}|}{r^{2}}

The Attempt at a Solution




I have to convert the values to be able to properly use the equations.
q1=6.60e-9 C
q2=1.41e-9 C
q3=-1.9e-9 C
d1=.03 m
d2=.02 m
k=8.9876e9

I think I will only need help with the first part, I then should be able to do the rest on my own.
between q1 and q2:
F_{e}=(8.9876e9)\frac{|6.60e-9||1.41e-9|}{.03^{2}}=9.29e-5to the left

between q1 and q3:
F_{e}=(8.9876e9)\frac{|6.60e-9||-1.9e-9|}{.05^{2}}=4.51e-5 to the right

I will now subtract the answers: (9.29e-5)-(4.51e-5)=4.78e-5
The force to the left is greater than the force to the right, so it will move to the left.

When I put this answer it says "Your response differs significantly from the correct answer."
The to the left part is obviously right.

What did I do wrong here?
 
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crybllrd said:
I have to convert the values to be able to properly use the equations.
q1=6.60e-9 C
q2=1.41e-9 C
q3=-1.9e-9 C
I haven't looked at the rest of your work, but these are not quite right. Realize that μ means 10-6, not 10-9.
 
Thanks a lot, I did have the conversions wrong.
I re worked it out and came up with the correct answer of 47.8 to the left.
Thanks again.
 

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