Directions: Assume, unless otherwise specified, that all numbers have at least 3 significant figures. You may work together, but make sure that you are working--not just watching. The magnitude of the force of attraction between the proton and electron in a hydrogen atom is: F = where e is the magnitude of the charge, k is a constant, and r is the radius of the circular orbit. Assume the proton is fixed in place and the electron is in a circular orbit of radius ri. The electron then "jumps" to a new, smaller radius r2. What is the change in the total mechanical energy of the system (in terms ri, r2, e, and k)? Hint: Use dynamics to calculate the kinetic energy for the electron in the initial and final orbits, then calculate the potential energy in both orbits (you will need to develop an expression for the potential energy and remember the force is attractive). Do you know what form the change in mechanical energy takes?

Directions: Assume, unless otherwise specified, that all numbers have at least 3 significant figures. You may work together, but make sure that you are working--not just watching. The magnitude of the force of attraction between the proton and electron in a hydrogen atom is: F = where e is the magnitude of the charge, k is a constant, and r is the radius of the circular orbit. Assume the proton is fixed in place and the electron is in a circular orbit of radius ri. The electron then "jumps" to a new, smaller radius r2. What is the change in the total mechanical energy of the system (in terms ri, r2, e, and k)? Hint: Use dynamics to calculate the kinetic energy for the electron in the initial and final orbits, then calculate the potential energy in both orbits (you will need to develop an expression for the potential energy and remember the force is attractive). Do you know what form the change in mechanical energy takes?