The lesson begins by outlining the work of some of the early experimenters and the sequence which eventually led to the realization of how a changeable electromagnetic field could be harnessed to other purposes. From there the lesson goes on to demonstrate how electric currents, magnetic fields and electromagnetic fields are so closely related. A simple hands-on activity is provided at the end of the lesson where students assemble an electric motor with simple materials. The lesson ends with a section in which the students are invited to discuss with the teacher, various ways in which they think these demonstrations could be improved.
8 – 18
- Gain a useful initial acquaintance with the most common elements of electricity and electrical equipment.
- Learn about how a rotating magnetic field, when interacting with suitably arranged coils of wire, can be made to produce a rotating mechanical force, i.e. an electric motor.
- Learn that a rotating magnetic field, when driven by a mechanical force, can produce an electric voltage, i.e. a generator.
- Learn that these two effects are generally speaking, equal and reversible.
- Learn about how these two phenomena can be conveniently and safely controlled.
- Learn about the importance of discipline and teamwork.
Anticipated Learner Outcomes
As a result of this activity, students should develop an understanding of:
- Basic direct current generators and motors
- engineering history
- problem solving
It is suggested that the students assist the teacher in obtaining the simple materials – small “button type” magnets, fiber discs and some 30 awg magnet wire and assemble them together to demonstrate how an electric motor works. The cost of these materials is minimal and each “motor” can be reused many times.
Alignment to Curriculum Frameworks
Curriculum alignment sheet is included in PDF.