- #1
Titan97
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Homework Statement
There protons are and two positrons are held such that two protons are on the ends of a diagonal of a square and the two positrons are on the ends of the second diagonal. The third proton is situated at the centre of the square. The system is released from rest. Find the kinetic energy of the three protons after a long. (Side of square is ##a##)
Homework Equations
$$F=\frac{ke^2}{a^2}$$
The Attempt at a Solution
I tried solving the problem by assuming that final potential energy is ##0## since all particles except the proton at the centre of square will move to infinity due to rulsions and initial potential energy is $$\frac{4ke^2}{a}+\frac{2ke^2}{a\sqrt{2}}+\frac{4ke^2}{\frac{a}{\sqrt{2}}}$$
But in solution given, they have state that only the positrons will fly away and the protons will remain. How is this possible?