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.

In my most recent lecture in Energy Conversion class, we discussed Power Factor Correction and Wattmeter Design.

I was also supposed to discuss effective resistance in ac networks, but there wasn’t enough time.

The first topic was about adding capacitors in a circuit to maximize power factor, minimize reactive power and required current in the original design.

From the Pythagorean power triangle, real power (which is the horizontal component) is constant.

The power factor, which is cosine of the angle between real power and apparent power (S) – the diagonal – will decrease along with S, based on the change in the total reactive power (Qt) which is the vertical component.

This is because the total reactive power has the capacitive Q deducted since it is pointed downwards, and would decrease Qt based on vector subtraction.

That was the main point of their computation, which several of the students missed out on when they arrived late, and they didn’t ask any questions during the examples that I gave, so when it came to the exercise, they only relied on their notes so the were getting confused trying to follow them to the letter.

The late students were looking for values that were in the examples that I didn’t give in the exercise, which was a combination of the concepts in the samples.

Here I used the reasoning the Executive Vice President himself gave to a student who arrived in his class well into the middle of the discussion, which was, “You don’t have the right to ask that because you were not here when we started the lecture.”

This means the student then has to ask his classmates first, before he asks the teacher.

Too bad a certain student never learned to be ashamed of asking his teacher like that.

Or maybe it’s just that he never thought such blatant questioning would have an adverse effect on his grade and how his teacher will judge his study ethics. Hopefully the terms under me have changed that impression.

Session 1679 believes the teacher is a robot, while fellow students are unreliable. Class dismissed.