- #1
nns91
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Homework Statement
A spherical potential conductor of radius R1 is charged to 20kV. When it is connected by a long, fine wire to a second sphere faraway. its potential drops to 12kV. What is the radius of the second sphere.
Homework Equations
V=kq/r
The Attempt at a Solution
So I know that R2= R1* (q2/q1). Thus, I need to find the ratio q2/q1. I am kinda lost in what to use to figure out q2/q1 ratio.
k*q1/R1 = 2x10^4 and k*q2/R2= 4x10^3 (because 2 spheres are equipotential at 12kV and sphere 1 drops 8kV so sphere 2 has to gain 8kV so initially sphere 2 is at 4kV)
k*q1/R1 = k*q2/R2 = 12x10^3.
With these 3 equations, I am still unable to figure out what is q2/q1. Can you guys give me some hints and suggestions ?