Which of the following terms refers to an object that orbits the sun and has enough gravity to be spherical but has not cleared the area of its orbit?

1. comet
2. asteroid
3. dwarf planet
4. planet

The nuclear potential that binds protons and neutrons in the nucleus of an atom is often approximated by a square well. imagine a proton conned in an innite square well of length 105 nm, a typical nuclear diameter. calculate the wavelength and energy associated with the photon that is emitted when the proton undergoes a transition from the rst excited state (n 2) to the ground state (n 1). in what region of the electromagnetic spectrum does this wavelength belong?