A12.5-cm diameter wire coil of 25 turns is initially oriented horizontally so that its plane is perpendicular to a magnetic field of 0.65 t pointing up. in an elapsed time of 0.15 s, the field is changed to one of 0.45 t pointing down. what is the average induced emf in the coil

Materials will have different energies associated with the electrons inside them. this is related to how strongly bound they are by their work function. if we sandwich a material with a very low energy between two materials with a high energy, we create a trap for an electron. if this trap is very narrow in one direction in comparison to the others, this is approximately a 1-dimensional box that confines the electron. what is the lowest energy of an electron in the box if the thinnest direction across the materials is 4.81 nm?