When an approaching magnet induces current in a coil, if the current is moving toward the magnet then is that the north pole of the magnet?

Question

I my students lesson: we coiled wire around a paper tube; connected the upper end so that if electrons flow through it a voltmeter reads negative; connected the lower end so that if electrons flow through it a voltmeter reads positive; I am instructing the students that if the voltmeter reads negative then the electrons are moving into the top wire thus approaching the magnet; I am instructing them that according to the left thumb rule that since the flow of the electrons are flowing upward when the voltmeter reads negative that their thumb would be pointing at the magnet and thus that is the north pole of the magnet.
If we flip it, all the opposite: positive reading, downward flow away from the south pole of the magnet.

This lesson covers a lot of high school science standards the way we're doing it, and even if I have the pole to flow direction incorrect it still works as a great functioning science paradigm. I'd like to write it up as a lesson for other teachers to do. Are there any inaccuracies that I need to be aware of?

By the way, this is a chemistry lesson, not physics. I like these types of activities because they get the kids more real experience with electron behavior. It's sort of setting up for long-term deeper thinking about electron repulsion, redox systems, ionization energies, etc...

Answer 1

If the positive lead of a bi-directional voltmeter is connected to the top of your coil and the negative lead to the bottom, then the meter will read negative if the electrons are trying to go up. The direction of electron flow (up or down) will depend on how the coil is wound; clockwise or counter-clockwise as viewed from above. If the north (seeking) pole of a magnet is brought into a vertical coil from above (increasing the downward flux), electron flow will tend to be clockwise as viewed fron above.