Location of zero net electric force

AI Thread Summary
The discussion focuses on determining the ratio of distances d_1 and d_2 at which particle 0 experiences zero net electric force due to repulsion from particle 1 and attraction toward particle 2. The relevant equation for electric force is provided, emphasizing the relationship between the forces and distances. The solution process reveals that the correct ratio is expressed as d_1/d_2 = sqrt(q_1/q_2), with clarification that the negative sign should be disregarded since it pertains to direction rather than distance. Participants confirm that the derived ratio is accurate, reinforcing the solution's validity. The final consensus is that the ratio d_1/d_2 = sqrt(q_1/q_2) is indeed correct.
gnarkil
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Homework Statement



Particle 0 experiences a repulsion from particle 1 and an attraction toward particle 2. For certain values of d_1 and d_2, the repulsion and attraction should balance each other, resulting in no net force. For what ratio d_1/d_2 is there no net force on particle 0?
Express your answer in terms of any or all of the following variables: k, q_0, q_1, q_2.

Homework Equations



electric force F = kq_1q_2/r^2 where k = 9*10^9, q_1 and q_2 represent charges in coulombs and r is distance in meters between point charges

Fnet = sqrt(F1^2 + F2^2) where F1 is repulsive force and F2 is attractive force

The Attempt at a Solution



Fnet = sqrt(F1^2 + F2^2)
0^2 = F1^2 + F2^2
-F2^2 = F1^2
-[(k*q_2*q_0)/(d_2)^2] = [(k*q_1*q_0)/(d_1)^2]
-(d_1)^2/(d_2)^2 = (k*q_1*q_0)/(k*q_2*2_0)
-d_1/d_2 = sqrt(q_1/q_2)
d1_1/d_2 = -sqrt(q_1/q_2)

correct ratio?
 

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There shouldn't be a negative sign when you're considering distance instead of displacement.
 
so aside from the negative sign, the ratio of d1_1/d_2 = sqrt(q_1/q_2) is correct?
 
gnarkil said:
so aside from the negative sign, the ratio of d1_1/d_2 = sqrt(q_1/q_2) is correct?

Yes.
 
okay thanks for the help
 
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