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 the second meeting of my mechanics lecture class for the tenth week of the second term, we had their second quiz on the topic of projectile motion.

Here I had only two questions divided into ten “minor” items each.

In the first one the initial velocity and initial angle were given, and various quantities such as the horizontal and vertical component of the velocity, and at what horizontal distance it returns to the original height, were asked. Included was searching for a specific time and displacement when one of the two component velocities was a particular value, as well as the maximum height.

One of the students asked if they had to get the first letter before they could solve for the second letter. I answered that it was up to them to analyze the equations provided to find out which one could be used to determine the values required.

I also had to give them the quadratic equation, although I said it was possible that they might not need it.

In the second problem, the starting angle of the projectile was given, as well as the required distance along the x-axis and along the y-axis that the object is supposed to reach. The first sub-question asked was the magnitude of the initial velocity needed to reach the “target”. For this one I had to tell them that they had to use a system of equations in more than one unknown, although from starting with four unknowns, they could break it down to three, two and one if they followed the example we used. In fact this was easier than that because they did not have to use reverse trigonometric functions and no second-degree variables either.

There were students who got stuck on that, and even asked me to give the value of the initial velocity so they could solve for the other items, but I declined.

I also reminded them that their problem sets were due on the next meeting, which, if they had practiced solving, would have given them a very good idea on how to solve the quiz problems. But I guess last minute laziness rules stated they could have done without it. Maybe they will think differently next time I give assignments like that.

I also said maybe they were regretting petitioning the subject out of turn, because if they had taken it with the regular classes, there would be more students and diligence against cheaters would not be so easy. They answered though that they were learning more in a small class. I don’t know how true that really is for this class actually.

Session 859 asks for the answer at this point, but the teacher refuses. Class dismissed.