I decided to deal with magnetic induction first. during the planning, I working through an explanation of the topic based on Faraday's law. But then I decided instead to use last year's TMA question about the transformer. I found that I could include Faraday's law nicely within this.
In practise, this provided a useful opportunity to discuss the merits of "remembering nothing - so there is less to forget in the exam"! The transformer equation is simply obtained directly from Faraday's law.
The lens calculation proved effective during the tutorial. Students were unclear about how to address even this simple two lens system. We discussed real and virtual images and the 'real is posiive' sign convention. I explained that the lenses are simply handled individually, in turn, working out image and then object distances.
The laser diffraction experiment went down very well. A student commented afterwards that he would have been disappointed if we had not done something like this - and he mentioned the value of our bouncing ball demonstration and discussion at the first tutorial.
The experiment task was to work out the ratio of the wavelengths of the red and green light from a laser pointer, using the grating equation. We also estimated the uncertainty. In fact we got exactly the ratio that is obtained from the wavelengths marked on the laser. This supported the uncertainty calculation of +/-0.01
Overall this seemed to be an enjoyable session, with a strong emphasis on using physical principles. I could repeat this next year.
After the session I had an email from a non-attender asking for information from the tutorial. I placed versions of the transformer and lens questions on the tutor group forum, with some tips to help guide the reader.However, there was no student discussion of this material and when I spoke to the student a couple of weeks later he had clearly not used the material.
[6 March 2013]