Electric Potential of 2 positive charges, and the speed

GenericPhy
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QUESTION 1

Homework Statement



Two positive charges, each with Q = +10 µC, are fixed to the x-axis at x = +a and x = -a, where a = 4 m.

(a) Find the electric potential at point A on the y-axis where (xA, yA) = (0, b) and b = 5 m. Take the zero of potential to be at infinity.

(b) A particle with charge q = -4 µC and mass m = 2.2 x 10-4 kg is released from rest at point A. Find its speed at the origin.

Homework Equations



Gauss's Law?

The Attempt at a Solution



I know I need to use superposition to calculate the potential at point A due the left-hand charge and add it to the potential at A due to the right-hand charge...
 
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Hello GenericPhy,
Welcome to Physics Forums!
GenericPhy said:

Homework Equations



Gauss's Law?
Gauss' law alone won't give you the solution to this problem. You need to look up the definition of electric potential. More-so, I'm betting that your textbook/coursework already has the equation for the electric potential of point charges already worked out for you.

The Attempt at a Solution



I know I need to use superposition to calculate the potential at point A due the left-hand charge and add it to the potential at A due to the right-hand charge...
Superposition. Yes, that is part of the correct approach. After you arrive at the correct equation for electrical potential, show us what you can do with it! :cool:
 
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