A ball is thrown straight up from height H while a second is thrown straight down. Neglect air resistance. After the balls have been released
(a) the one thrown up has the greater acceleration.
(b) the one thrown down has the greater acceleration.
(c) the accelerations are the same.
(d) neither ball accelerates after it has been released.
p

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?