a student places a 10 g coin on a disk at a point 0.02 m from the center of the disk. the student rotates the disk with a steadily increasing speed. at what speed will the coin start to slide off the disk if the coefficient of static friction between the coin and the disk is 0.47?

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?