• Activity 2
Electric motor operating principle
Objective:
Students experience the existance of Lorentz force and get acquainted with the principle of
operation of the electromotor.
Materials/Devices:
Horseshoe magnet, straight conductor, stand, electricity source, computer, internet
Procedure:
Teacher explanation about the force acting on moving charges in magnetic fields (F=B . l . I)
Students working in groups of 5 do the experiment (Demonstartion of Lorentz force)
Students explore the information on the Internet and get acquainted with the principle of
operation of the electromotor, then prepare a short presentation about it.
Method:
Following the teacher’s explanation students demonstrate the Lorentz force with the help of
the materials/devices for the experiment. Teacher helps where needed. During the experiment
students cooperate, discuss and interpret the procedure.
It is essential that students understand the information they find on the Internet during
exploration and share it with the groups. TH planning and execution of the presentation helps
in the process.
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