Student "edition" found at {csi dot journalspace dot com}.

Maybe I shouldn't have started this blog now, not with everything that's been going on.

On the third day of the ninth week of classes we had our fifth experiment in Introduction to Electricity and Magnetism lab, which was Kirchhoff’s Rules.

I had my first challenges of the day during the ten-minute quiz at the start of the meeting. Deiv (who else) questioned why we had to have the quiz and at that time, which is ironic because it was he who reminded me the meeting before the first experiment about the quiz – or rather asked me about it, and I remembered.

I told him that the quiz was to ensure that the students read about the experiment before showing up in class, and that they were not late, which is a perennial habit of students enrolled in the three-hour lab period.

This time, he was questioning that one (actually two) of the items in the quiz was stating two of Kirchhoff’s rules. He asked why I couldn’t just have stated the rule and asked them to identify it. I told him that the items could be about any portion of the experiment (theory or procedure) to keep the students on their toes as to reading the whole experiment.

Next he asked about a relationship I was asking between the number of unknown currents and the number of loops to use in the circuit. I recalled for them the types of relationships between numbers: equal, greater than, less than etc. He would not stop though, and still asked me to give them possible answers to choose from.

Unlike our previous sessions, wherein after the quiz I let them proceed straight to borrowing the equipment and performing the experiment on the assumption that they had read up on the procedure, this time I predicted that there would be several questions about getting the theoretical values of the voltage and current they were supposed to measure so I preempted those by having a short lecture at the start. I also warned them that the concepts discussed will be taken up in more detail in the lecture, so they had better pay attention.

I dissected the node or junction (or current) rule and the loop (or voltage rule) into the equations necessary for them to solve for the unknown currents (in this case three), using letters for the points and nodes, and creating the convention that the order of the points in the loop would also determine the direction of the loop or the arbitrary current. I also had to tell them that if the computed current is negative, that means their designated direction is opposite.

To ensure that each group made their own computations, I assigned their current directions and loops, different from each group, but the answers would be the same in the end.

The power to session 686 will have to be cut short here. For now, class dismissed.