A 500g cart moving at 0.25 m/s collides and sticks to a stationary 750g cart. How fast do the two carts move after the collision? Sketch a diagram and use vectors to represent the velocities.

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?