(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

The work function (energy needed to remove an electron) of gold is 5.1 eV. Two pieces of gold (at the same potential) are separated by a distance L.

For what value of L will the transmission probability for an electron to cross from one to the other be T ≈ 10-3? Assume that G = 1 in the formula for the tunneling probability.

2. Relevant equations

T [tex]\approx[/tex] G*e^{-2KL}

where K=2*pi*[tex]\sqrt{((2*m)/h^{2})*(U_{o}-E))}[/tex]

T: Tunneling Probability

m: Electron Mass

U_{o}: Potential (the work function in this case)

E: Energy of the electron

L: Length of the potential barrier to tunnel

h: Planck's constant

3. The attempt at a solution

It seems to be a simple plug and chug, but how do I find the energy to use in the (U_{o}-E) part in the tunneling equation?

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# Tunneling w/ unknown energy

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