(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Four idential charged spheres are located at the corners of a square with side length 2a. The spheres are much smaller than the size of the square (r<<a) and each sphere has a mass m and carries the same charge -Q.

a) What is the total electrostatic potential energy of the combined 4-sphere system when arranged as described?

b) How much kinetic energy does a sphere gain by moving very far away from the other three?

c) What is the speed of a sphere moved very far away?

2. Relevant equations

Utot=kq1q2/r

KEf=Ui

KE=1/2mv^2

3. The attempt at a solution

For part a, I think i got the right answer: Utot=k(4root2q^2+2q^2)/root2r

b)KE=1/2(4m)v^2 and thats it because thats all we know

c) I used Ui=Kf

so k(4root2q^2+2q^2)/root2r=1/2(4m)v^2

and solve for v to get

v=squareroot(k*2q^2/mr+q^2/root2mr)

1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

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# Homework Help: Electrostatic Potential of 4 charged spheres on corners of a square

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