This week’s lectures have been about the response of networks to a sinusoidal drive and how to analyse them. First of all, this involved using an incredibly difficult method based on solving differential equations (so difficult that the attempt terminates part way through after much baffling mathematics), a “sneaky” approach based on complex algebra and finally a “super sneaky” approach based on the impedance model.
This final method turns all of the steady state sinusoidal circuit analysis problems which seemed pretty difficult using the first two methods into problems which can be rather more simply solved by the application of Ohm’s Law, along, of course, with all of the usual circuit analysis techniques based on the node method, Thevenin, Kirchoff et al.
I think if we hadn’t been warned that the conclusion of the week was going to be relatively straightforward I might have been tempted to cut my losses and plough straight on into week 11 – but I’m glad that I didn’t. In the end, the lab and homework problems seemed to be fairly tractable once I’d thought about them properly – and been guided by the odd hint or seven from the discussion forum of course!
I now have the magic 59% mark showing up on my profile page – which, even if I complete the next two weeks homework and labs, I won’t be able to improve on until the final exam. Despite many pleas from students to the course team on the discussion forum, they still appear to be keeping silent about the form the final exam will take, when it will appear, how long we’ll have to complete it in and so on.
Not knowing when the final exam will appear is pretty frustrating, as one of the “joys” of being a part-time distance learner is that the rest of life tends to get in the way of study, in exactly the way it doesn’t when you’re full-time at a brick university.
One of the lessons therefore that the MITx/edX team ought to take from this first run of 6.002x is that certainty over the time windows for assessments at or very near the start of the course is essential. Without such certainty, it’s difficult to see how edX would ever get future students to pay for assessment, even if the delivery of course content remains free.