(a) Calculate the velocity of the electron in the ground state of hydrogen. Express your answer as a percentage of the speed of light in a vacuum. Show that the total energy of the electron is equal to the negative value of its kinetic energy. Calculate all energies in units of electron volts. [5]
(b) The electron in a hydrogen atom is replaced by a muon, which has a mass approximately 200 times greater than that of the electron. Calculate the wavelength of the n=2 to n=1 transition in muonic hydrogen. In what part of the electromagnetic spectrum does this transition belong? [9]
(c) An excited electron in a singly-ionized helium atom (He+ ion) makes a transition from the n=6 state to the n=2 state. Calculate the energy of the emitted photon in the Bohr model. Determine whether or not this photon could be absorbed by a hydrogen atom in its ground state. [5]