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Homework Statement
Two initially uncharged identical metal spheres, 1 and 2, are connected by an insulating spring (unstretched length L0 = 1.55 m, spring constant k = 30.0 N/m), as shown in the figure.
Charges +q and –q are then placed on the spheres, and the spring contracts to length L = 1.250 m. Recall that the force exerted by a spring is Fs = kΔx, where Δx is the change in the spring's length from its equilibrium length. {Correct Answer: a. 3.96e05 C, b. 1.55 m}
(a) Determine the charge q.
(b) If the spring is coated with metal to make it conducting, what is the new length of the spring?
Homework Equations
1/4πε0 * q1*q2/r^2
f = kΔx
The Attempt at a Solution
I set fe = fs and got my answer for letter a as 3.16*10^5 C, which is incorrect from the actual answer. Not sure why it's .8 difference in value. For letter b, I have no idea how to do b.
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