Which of the following statements about floating objects is always true? a. the object’s density is greater than the density of the fluid on which it floats. b. the object’s density is equal to the density of the fluid on which it floats. c. the displaced volume of fluid is greater than the volume of the object. d. the buoyant force equals the weight of the object

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?