The time for a proton to reach a certain velocity

AI Thread Summary
The discussion revolves around calculating the time required for two protons to reach a velocity of 1 m/s in a nuclear fusion context, where the protons are influenced by their electric fields. Participants are confused about whether to use the diameter or radius to determine the distance between the protons and how the electric field affects their motion. There is a suggestion to treat the system as a single-vector problem, simplifying the analysis of acceleration. The conversation emphasizes the need for clarity on the original problem statement and the application of Coulomb's law. The complexities of electric fields in this scenario highlight the challenges in achieving fusion conditions.
dirb
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Homework Statement
Find the time so the proton reaches 1 m/s
Relevant Equations
Coulomb's law
A nuclear reactor is built to fuse two hydrogen atoms that are already ionized to protons. However, the electric field of the protons are becoming a significant obstacle. If the reaction was to be defined as H2--> 2H++2e-, if the mass of a proton is mp, the radius of a proton r the charge of an electron is e and the coulomb constant k. How fast should the two protons reach 1 m/s so that they touch? Assuming that the protons have a straight path

Can anybody give a hint on what concept I should use? I was thinking of energy and momentum which I am unsure of, though the most confusing part for me is the distance of the protons, should i use the diameter instead of the radius?
 
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I don't understand how the electric field can be both "a significant obstacle" and "negligible" ##-## can you please post the complete and exact original problem statement, along with your attempt at a solution?
 
sysprog said:
I don't understand how the electric field can be both "a significant obstacle" and "negligible" ##-## can you please post the complete and exact original problem statement, along with your attempt at a solution?
Sorry, It was supposed to be "assuming the electric field doesn't change the proton's straight path."
 
dirb said:
Sorry, It was supposed to be "assuming the electric field doesn't change the proton's straight path."
That seems to me to mean that we can treat the system as single-vector, which means that we can see the acceleration as the second derivative of position wrt time, without bothering with a tensor system, but I'd still like to see the original problem statement, and your attempt at a solution.
 
dirb said:
Homework Statement:: Find the time so the proton reaches 1 m/s
Relevant Equations:: Coulomb's law

the distance of the protons, should i use the diameter instead of the radius?
Presumably you are taking the charges to be effectively points at the centres of the protons. So how close do those get?
 
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