There were a couple of moments in the first-year lab yesterday that made me want to despair:
The first one:
Student: My magnetic field doesn’t change when I increase the current
Me, seeing what the problem is: How do you connect an ammeter in a circuit?
Student: In series. Um…oh, hang on…we’ve done parallel, haven’t we?
The second one:
Student: We’ve switched it on, but nothing’s happening.
Me, seeing that the red ‘on’ light isn’t on: Is it plugged in?
At this point I could have despaired – how can we possibly teach students who can’t plug something in or put an ammeter in series with what they want to measure. But, I haven’t, because I also teach in the third year labs, where things often are at the other extreme – e.g. students suggesting ways of improving the experiment – and sometimes actually going and doing it. Last week, we were working with a ferrofluid (a magnetic fluid – pretty cool stuff) and a pair of them, while waiting for their experiment to settle, decided that a good way to fill the time would be to build the biggest electromagnet they could out of what they could find in the lab and see how the fluid responded to it. I think that shows some initiative, some real understanding of physics (since they went on to build the thing) and actual ability to do experimental work for themselves. The result was a little bit messy but quite interesting.
So we have students who perhaps can’t plug in an ammeter properly in year 1 turning into real physicists by the end of year 3, so that’s no cause for despair, really.