Two protons that are very far apart are hurled straight at each other, each with an initial kinetic energy of 0.17 MeV, where 1 mega electron volt is equal to 1106 (1.610-19) joules. What is the separation of the protons from each other when they momentarily come to a stop?
? m
I have tried the electric force equaton, but I just can't get the right answer
2007-07-01 13:34:02 · 1 answers · asked by Anonymous in Science & Mathematics ➔ Physics
They will come to stop when the potential energy of the electric force equal the initial kinetic energy. The electric potential energy is q1*q2 / 4π*e0*x, the kinetic energy is 2*0.17MeV.
1 eV = 1.6*10^-19 J, not 1 MeV see http://en.wikipedia.org/wiki/Electron-volt
The energy at distance x is (qe^2 / 4π*e0) / x = 1.438*10^-9 eV*m / x
x = 1.438*10^-9 / 0.34*10^6
x = 4.229*10^-15 m
2007-07-01 13:49:35 · answer #1 · answered by gp4rts 7 · 2⤊ 1⤋