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(U2/(E(U-E)))sinh2([tex]\alpha[/tex]L)) [tex]\alpha[/tex] = ((2m(U-E))1/2)/h 3. The attempt at a solution I get 0=x-x2-.25sinh2([tex]\alpha[/tex]L) this is after I make E/U=x. How can i solve for x and then solve for E?