The Problem: A small metal bead, labeled A, has a charge of 25 nC. It is touched to metal bead B, initially neutral, so that the two beads share the 25 nC charge, but not necessarily equally. When the two beads are then placed 5.0 cm apart, the force between them is 4.5×10−4 N. Assume that A has a greater charge. What is the charge q_A and q_B on the beads?
Solving:
I know I need to use Coulomb’s Law
F=(K*q_A*q_B)/r^2
This is what I think all the variables are, based on the problem:
K is a constant = 8.99*10^9
r=0.05 meters
F=4.5*10^-4
What do I do from here? I don't know how to incorporate the 25*10^-9 given to me in the problem, because it says it is shared unequally. Help!
Solving:
I know I need to use Coulomb’s Law
F=(K*q_A*q_B)/r^2
This is what I think all the variables are, based on the problem:
K is a constant = 8.99*10^9
r=0.05 meters
F=4.5*10^-4
What do I do from here? I don't know how to incorporate the 25*10^-9 given to me in the problem, because it says it is shared unequally. Help!
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Solve the equation in terms of q_a and q_b. You then have two equations for q_a and q_b since q_a + q_b = 25 nC. Solve the two equations using a matrix