Teaching how to think physics

One of the things I frequently bleat about is that physics isn’t synonymous with stuffing numbers into formulae. Therefore, it’s with some horror that I’ve watched through my attempts at doing the 2012 NZQA Scholarship Physics exam and seen myself stuffing numbers into formulae. At least, that is how many of the videos come across to me. I’m left thinking why. I mean, I know you can’t answer a scholarship physics exam if you think it’s about plugging-and-chugging. You need to know your physics to know what mathematical relationships may or may not be required, and how to use them.

I think the problem with these videos is that they haven’t captured what I have been thinking. WHY have I chosen to use a particular expression to relate X and Y? What sometimes comes across is that I’m picking the relationships out of thin air. HOW do I know they are the ‘right’ ones to use? That I’ve often not made clear. I think some viewers might be frustrated here – they can do the solve the equations and plug-and-chug bit at the end, what they can’t do and need help on is identifying exactly what needs solving and plugging. That skill is really hard to teach. Partly, I think, this is down to being an ‘expert’ in the area. It is really hard to explain thought processes when they are second-nature to you. Perhaps more powerful would be to give the paper to a couple of good first year students and get them to work through it.

Or, maybe more powerful still, give some ‘experts’ some yet tougher problems to work through. Things that really stretch their thinking. A quick survey of some of the PhD projects going on here would, I’m sure, unearth a number of really tough problems that need some solutions. Give one of those problems to a small group of physicists (and, realistically, other flavours of scientist) and get them to discuss it together. Now, there’s an idea for some more videos.

If you want to see some physics-without-the-equations taking place, here’s a Walter Lewin lecture on rainbows that came to my attention recently. There’s a teeny-weeny amount of maths in it, but you can really ignore that if you want to. It’s a long lecture but really good. Much better than the usual Friday night television. http://www.youtube.com/watch?v=FJVvtOy-ukE .Enjoy. As for me, I’m off to the swimming pool.


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