Me plz i don't understand my science hw

Aregion of space in which a measurable gravitational force is indicated by the force exerted on a test mass is called

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?

What is the moment of inertia i of this assembly about the axis through which it is pivoted? express the moment of inertia in terms of mr