Show that the circumferential strain measured by a transverse gage on a round bar is the same as the radial strain. Explain why this is consistent with our definition of Poisson's ratio equal to the ratio of perpendicular strain to parallel strain.

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?