Science

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. 

Science, evolution and creationism (again)

I have written before about creationism and science education, and how it is not mentioned in Junior Cert Science. Every so often these surveys appear in the papers; this one was in the New Scientist last May. Researchers polled a random sample of nearly 2000 high-school science teachers across the US in 2007:

[ ] asked about the teachers’ personal beliefs . . . 16% of the total said they believed human beings had been created by God within the last 10,000 years.

I guess the number shouldn’t be surprising, but I can’t help but feel a little uncomfortable.

Ten great ideas revisited

The amazing thing about our science education is not that so many run away from it, but rather that any at all stick with it. We really do an exceptional job of sucking out all the good stuff.

There must be a website out there somewhere concentrating on the most wonderful ideas in science for the non-specialist, but I haven’t been able to find it.

So I’m going to do one.

Ten ideas. I’m sure the number will grow. Then link each to relevant external resources; these must be interesting, informative and aimed at an appropriate level.
For project work I could maybe get students to pick one which interests them, research it in detail and report back to the class.

Because I am fascinated by science, and am sick to death of teaching students how to measure the density of a stone.

I have put together a word document on this for a recent Fourth Year test; it’s a start.

Fun with the Van der Graff and Animoto

A study of concentration

We had the usual fun with the Van der Graff today. The weather was rather accommodating, and it tallied nicely with the last class before the long weekend.

I have never got a student’s hair to stand up dramatically, but i was drying the canvas belt with a hairdryer when I realised I could help things along a little by aiming it upwards into Fania’s hair. It loosened up the hair very nicely and the show was much more impressive as a result. I also got a student to hold up a mirror so Fania could see for herself what everyone else was laughing at.

I have seen a few examples of Animoto and how it does a pretty cool job of presenting photos, so I thought I’d head on over and check it out.

It really is pretty impressive, and very user-friendly. There might be a couple of thinks I would change, but then again that may just be me not familiar with the program.

It allows for automatic uploading to youtube, which was a pleasant surprise. The free version limits the clip to 30 seconds, so I might just invest in the longer version to check it out.

This is a clip I uploaded last year

 

When is a kilogram not a kilogram?

Many physics students will be familiar with the fact that the prototype kilogram is kept in a high-security vault in Paris. What I didn’t realise was that the mass of this specimen is changing, albeit very slightly.

So here’s the question; if this is the one and only true version of the kilogram, and it loses mass, doesn’t it still stay a kilogram?

And doesn’t that mean that other copies, which would have been correct originally, are now wrong?
(I think in fact that they may all be losing mass slightly.)

Something very unscientific about all this . . ., no wonder physicists are embarassed about it.

Seems a bit like when kids make up the rules of a game, and when it turns out that these don’t suit the leader of the gang, he just changes them.

Which seems as good an excuse as I am likely to get to show Eddie Izzard – Do you have a flag?
 

 

More youtube and some Flickr

Decided it was time to see what I could do with Flickr, so I spent the day taking photos of Junior Cert Science demo apparatus. The plan is that I will show this to students and they will have to name the demonstration. Hopefully it will help the second-years revise for Summer exams. It must be rather daunting to have to go from a year of short class tests, to a set of formal exams which require knowledge  taken in over the whole year.

Students can hopefully access this themselves if they wish, although I may  print it off for those who don’t have the facilities.

Bloody nice spectrum though innit?

Thanks Conor!

Of course there’s still the bread ‘n butter leaving cert material:

 

Laptops from €249

This form Dell

Laptop Computer

From €249 plus delivery.

I don’t know the specs but I reckon they would be ideal for working with dataloggers in Science projects like Scifest and Young Scientist, and I can’t imagine they are more expensive than the alternative mobile dataloggers; LabQuest and Xplorer GLX

You would still have to use their software and sensors, but still . . .??

The Ideology that dare not speak its name

The January edition of Science Spin included a supplement on choosing science as a career. I was asked to contribute my thru’penny bit as a science teacher. Most of the other contributors included their opinion of what science is, but either I wasn’t asked or, more likely, my reply was too boring to print. So here’s what I should have written:

Science is many things, but the more I find out the more I believe that Science is a tool used to maintain the inequality that exists between the First and Third world. It is  an instrument used to develop the military technology which enforces this inequality, and which in turn is fed by the unequal distribution of the world’s resources.

One of its strengths lies in its refusal to acknowledge its role in this. Indeed the mere questioning of this can label the critic as an ‘outsider’ and consequently negate the message or its potential validity.

For an example of this  look no further than the  manner in which the role played by war has influenced so many developments in Science, and how this is conveniently ignored for the sake of a more sanitised and noble picture which is what you will find in your school science text-book.

Now why couldn’t I think of that at the time?

It’s also only fair to acknowledge that the article was both interesting and very well written by Marie-Catherine Mousseau. It described very well the wide spectrum of careers available for graduates in Science. The magazine itself is also very impressive. I genuinely hadn’t read it in years but its production is top quality and I will certainly be checking it out again. See for yourself if you get a chance. In all good bookshops, as they say.

Science Spin

Henry Reed: Naming of Parts

One of my favourite poems is Naming of Parts, by Henry Reed. It encapsulates so much of what is wrong with our education.

It is about an army instruction lesson on the parts of an army rifle, where the poet is half listening to the instructor, and half looking outside the window at the beautiful japonica flowers. For me some of the best lines are here:

And this
Is the upper sling swivel, whose use you will see
When you are given your slings. And this is the piling swivel,
Which in your case you have not got.

So many Physics concepts are interconnected and we often find that we teachers introduce one concept in terms of others which students have still not covered and are therefore not familiar with.

Of course the more obvious message is the contrast between the dry-as-dust lesson and the wonderful world outside.

It’s also nice to read the comments below the poem; different people take completely different messages from it. And of course there is no one ‘right’ answer or interpretation, in spite of the answers which (some of) my English teachers wanted me to learn off so many years ago.

Henry Reed and Frank Duncan reading “Naming of Parts” here

Film adaptation of poem here

 

Youtube – is it just me?

I have had access to youtube in my classroom since last September and it is by a country-mile the geatest ICT resource I have in my arsenal.

You could take away the Interactive Whiteboard, the dataloggers and the DVD player, but I would cry if I lost youtube.

The irony is that I bought a VHS-to-DVD converter last year and it has taken me a full year to convert all my library. At the time I had probably 75 programmes, many on the same VHS cassette, and I was excited at copying each program on to a seperate DVD for easy access.

The big advantage of DVD was that I could scroll straight through to whatever part of the program I wanted – no more rewinding and fast-forwarding. I was also considering putting everything from there onto a large external hard-drive, for even easier access. All of this would take an inordinate amount of time, but would at least encourage me to use the resource more, where previously I would use it sparingly because of the hassle.

I think that for many students a video of anything more than ten minutes would lose their attention.
Hence my fascination with youtube.

This resource is available to everyone, there doesn’t seem to be anything too dodgy on it, or at least if there is it isn’t thrown at you; you would have to go looking for it.

All clips are under ten minutes. My favourites are Quantum Physics clips, because this stuff is not on any leaving cert syllabus (except maybe Religion) and the comments themselves are often revealing.

I wish I had this resource when I was growing up. If nothing else it allows me to see there are so many people out there who are as fascinated by science as I am, and unlike text-books and teacher conferences these people are all only too happy to express their wonder. It really is inspiring.

There are also wondeful demonstrations which can I can incorporate into my own lessons, and the videos usually include all those small but vital bits which text-books and demonstration-books often omit.
I feel like crying when I realise this resource is blocked in most schools.

I have spent quite a while loading up my favourite clips onto the online favourite program delicious.

CESI (Coputer Education Society of Ireland) are having their conference next month so my homework over the next week is to put together ten top reasons for unblocking this site.

Or is it just me?

del.icio.us site tagged with my youtube links are here
CESI
 homepage