The radius of each wheel on a bicycle is 0.400 m. The bicycle travels a distance of 3.0 km. Assuming that the wheels do not slip, how many revolutions does each wheel make? (a) 1.2 103 revolutions (b) 2.4 102 revolutions (c) 6.0 103 revolutions (d) 8.4 104 revolutions (e) Since the time of travel is not given, there is not enough information for a solution.
Lecture 15 2 How to produce B-field • Changing E-field • Electric currents • flowing electrons • nuclear and electron spins and orbital motion Magnetism in a materials ▪ Paramagnetic materials (amplify the external B-field) ▪ Diamagnetic (decrease the external B-field) ▪ Ferromagnetic (amplify, remain) ▪ Strongly interacting atoms & electrons ▪ Quantum & classical effects March 2, 2015 54 Magnetization • Electrons and ions have magnetic moments • No B-field: randomly oriented B Magnetization Paramagentic B Diamagnetic Magnetization Ferromagenic