Solving Elementary Charges Homework: Find # Electrons Transferred

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To solve the problem of electron transfer between two charged spheres, first recognize that bringing the spheres into contact allows charge to redistribute until they reach the same potential. Sphere A has a charge of -3q and Sphere B has +5q, resulting in a total charge of 2q after contact. The number of electrons transferred can be calculated using the equation Q=Ne, where e is the elementary charge. The calculated number of electrons transferred is approximately 1.1 X 10^4, indicating that electrons move from Sphere A to Sphere B. Understanding the direction of charge flow is crucial, as the negative charge from Sphere A neutralizes some of the positive charge on Sphere B.
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Homework Statement


Sphere A with charge -3q is 1.5 m from another identical sphere B with charge +5q. The two spheres are broughtinto contact and then separated by a distance of 1.5 m; the magnitude of the force between the spherees is 8.1 X 10^-2 N.
a. Find the number of electrons transferred from one sphere to the other. Explain which way they moved.


Homework Equations


Q=Ne (e=1.602 X 10^-19)


The Attempt at a Solution


I don't really understand the problem. What does it mean when it says that "the two spheres are brought into contact and then separated...". Do i take the average of the charges? The answer for the number of electrons is 1.1 X 10^4. Please help.
 
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What will happen when the two spheres come together? One has positive charge and one has negative charge. Hmm, do you think that maybe charge will flow? Which direction?

Use Coulomb's law which is:

F= \frac {Q_1 Q_2} {4 \pi \epsilon d^2}

to get the absolute amount of charge of different sign. Keep in mind that the charge that moves will combine with the positive charge and isn't counted.
 

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