10. Jane puts the north pole of a bar magnet near an object on her desk. As the magnet gets closer to the object; the object is repelled and moves away from the magnet. Which of the
following statements about the object on Jane's desk is true?
a. The object is not made of metal.
b. The object has randomly-arranged domains.
c. The object has a north pole but no south pole.
d. The object is a magnet or has been magnetized.

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?