Modern physics: Atomic Structure

In summary, the conversation is about calculating the average potential energy of an electron in the ground state of hydrogen due to the Coulomb interaction with the nucleus. The relevant equation is V(x) = -(e^2) / [4(pi)(epsilon naught)(delta x)]. The Bohr radius is used as the average radius of the electron wave function, and the electron charge (e) is used in the equation. However, when the mass of the electron (0.511 MeV) is substituted for e, the units do not match. This shows that e in the equation represents the electron charge, not mass.
  • #1
ira
2
0

Homework Statement


If we take the average radius of the electron wave function in the ground state of hydrogen to be the Bohr radius, calculate the average potential energy of the electron due to the Coulomb interaction with the nucleus. State answer in eV.

Homework Equations


I think the relevant equation is V(x)= -(e^2) / [ 4(pi)(epsilon naught)(delta x) ]

The Attempt at a Solution



1/[4(pi)(epsilon naught)] = constant = 8.9876x10^6
The Bohr radius= 5.29x10^-11 m <--- (is this delta x?)
e = 0.511 MeV =5.11x10^5 eV (is this even correct? does 'e' mean the electron charge or mass?)

V(x)= [[-(0.511)^2] . (9.9876x10^6) ] / 5.29x10^-11
=4.436x10^28

As you can see I have many doubts. Hope any of you physics genius can help!
 
Physics news on Phys.org
  • #2
ira said:
e = 0.511 MeV =5.11x10^5 eV (is this even correct? does 'e' mean the electron charge or mass?)
What do you expect in a formula for the potential of a charged object in the field of another charged object?

Just work with units, then you'll see what went wrong.
 
  • #3
So, does e mean the mass of electron?
 
  • #4
Do the units match if you plug in a mass?
 
Back
Top