What is the relationship between wavelength and energy to an electron in an atom orbit? From this law: $2\pi r=n\lambda$. if the radius of the atomic orbit increases the wavelength of the electron will increase.
And if the wavelength increase the energy will decreases due to: $E=hf$.
But actually the energy of electron increases if energy level increases!!
 A: Strictly speaking, that relationship only works for a particle in free space without any sources of potential energy. In this specific case, you can do a pretty good job by assigning  that component to the kinetic energy of the electron, and then adding in the (negative) potential energy, which is smaller for wider orbits. 
If you want to do things correctly, though, you need to be solving the full time-independent Schrödinger equation, which tells you among other things that, in the presence of a potential, the wavelength changes from point to point, so things are a bit more complicated than in the naive calculation. 
A: Expanding on @EmilioPisanty excellent answer, once you have solved the full Schrodinger equastion you can calculate the expectation values of the kinetic energy operator and the potential operator.  The sum of the two is the eigenvalue of course, but the separate values give you a handle on the average kinetic and potential energies of the orbital.  Then you can infer an average wave length from your classical equations.
