A proton is bound in a square well of width 3.3 fm= 3.3 ×10−15m. The depth of the well is six times the ground-level energy E1−IDW of the corresponding infinite well.

If the proton makes a transition from the level with energy E1 to the level with energy E3 by absorbing a photon, find the wavelength of the photon.

lembda = _______m