I am doing science with my 6th grade son, and there is a circuit with an electromagnet (as below)
When asked to describe the energy conversion when the switch is turned on, part of the answer provided by the teacher indicates that electric energy is converted into kinetic energy when the electromagnet attracts the hinge.
Ignoring the obvious complications in understanding how magnets work (I am sadly still confused about that), this statement seems wrong for the following reasons:
- A magnetic field is created which attracts the hinge. There is no direct conversion from electric energy to kinetic energy.
- Any energy conversion seems to have been from the chemical potential energy in the battery to the current flow. The movement of the hinge seems to be an indirect effect rather than a direct conversion.
- Is there is additional resistance added by the presence of the electromagnet? If not, there should be no energy loss, if yes, what's the mechanism of that loss?
Clarifications will be very much appreciated, I tried to work through the above questions with my kid but ended up being very confused myself.
Lastly, if someone can share an answer that will be appropriate as an answer in a 6th grade exam, yet technically correct - that will be great. :)