5.1 - quick application of Lorentz force
5.3 - Thomson's cathode ray experiment
5.4 - force on square wire loop
5.5 - surface and volume current in a wire
5.6 - rotating charged disc or sphere - find surface and volume currents

Bonus questions

5.7 - show that the integral of J over volume is dp/dt
B1.1 - Write down and solve the equation of motion for a charged particle in arbitrary uniform B and E fields (ie, not 'crossed')

Examples class problems

5.2 - trajectory of a particle crossed E and B with different initial velocities
5.39 - Hall effect