Calculating Net Force from Charges

AI Thread Summary
To calculate the net force between two charges, use the formula F=KQ1Q2/r^2. If there are more than two charges, calculate the force between each pair and then sum these forces using Fnet=F1+F2. This approach ensures that all interactions are accounted for. Understanding the distinction between calculating forces for two versus multiple charges is crucial for accurate results. Proper application of these formulas leads to a correct determination of net force in electrostatic scenarios.
Gardalay
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If I have two different charges and I'm told to calculate net force, do I just use F=KQ1Q2/r^2 or Fnet=F1+F2...
Please explain.
 
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Gardalay said:
If I have two different charges and I'm told to calculate net force, do I just use F=KQ1Q2/r^2 or Fnet=F1+F2...
Please explain.

If you have two charges at a distance 'r' then it is just F=KQ1Q2/r2


If you have more than two charges, you'd need to find the force between each pair of charges and then find the resultant force using Fnet=F1+F2
 
Ahh ok thanks
 
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