A one-dimensional quantum well of width 19 nm is created, and measurements show that the energy difference between the ground state and the first excited state is 0.19 eV.
What is the eﬀective mass of the electron in the well?
Answer in units of kg.
It finds the effective mass of electron in the infinite quantum well. The solution is detailed and was rated '5/5' by the student who posted the question originally.