The mystery of magnetism

Floating rings used to demonstrate magnetic repulsion
Floating rings used to demonstrate magnetic repulsion

Sometimes the most basic question can be the hardest to answer. “How do magnets work?” is one such question. If you’re a teacher like me you’ll probably end up using fancy terms like “North and South Poles” and “Opposite Poles Attract”, and may even go on to demonstrate it using the floating magnets above.

Or if it’s a senior class you might talk about the material having “Magnetic Domains” which are usually randomly oriently but in a magnet are all lined up parallel.
And this invaribly works.
But there’s usually one student (quite often it’s someone who is not great academically, and consequently may remain in the background for much of the time) who’s not happy with this. 
But how does one magnet know that the other magnet is there?

And that, my friends, is a great moment. It means that at least one person in my class managed to avoid all the ‘education’ that I stuff down their throats, and maintained his ability to think for himself. ‘Course that won’t help him (or her) much when it comes to exam time, but at least in my mind it counts for a lot.

A former student once sent me a card on which he wrote “Thanks sir, I was in your class for two years and in that time I learnt nothing”. It was one of the nicer compliments I have received. Cheers Luke.

I hope to be teaching more Junior Cert Science this year and need to remember to avoid the temptation of throwing in jargon as a substitute for deeper explanations. For that matter, when the apple falls from the tree how does it ‘know’ which way is down?

Or here’s one for leaving cert students: why is the charge of a proton (which is composed of three quarks) the same as the charge of an electron if they are completely seperate particles?

Here’s a lovely article taken from the  science magazine Discover detailing how the author realises that nobody actually understands how magnetism works.

As teachers, we need to become comfortable discussing the limitations of what we know. 
Advertisements

2 comments

  1. Thanks for that.
    The link was in originally but every so often wordpress doesn’t seem to want me to use paragraphs, and in playing with the code I must have lost the hyperlink.

    Noel

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s