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

What energy (in eV) should a beam of electrons have so that 0.1% of them are able to tunnel through a barrier of height 7.0eV and 1.0 nm wide? Start with the equation for T(E) and set it up with 1/T(E) on one side and let E/U=x for the unknown. Solve the equation for x and then E.

2. Relevant equations

T(E) (1+.25(U^{2}/(E(U-E)))sinh^{2}(_{[tex]\alpha[/tex]}L))

[tex]\alpha[/tex] = ((2m(U-E))^{1/2})/h

3. The attempt at a solution

I get

0=x-x^{2}-.25sinh^{2}(_{[tex]\alpha[/tex]}L)

this is after I make E/U=x. How can i solve for x and then solve for E?

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# Homework Help: Solving for energy involving hyperbolic

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