## Helping with physics

| family

J-‘s grade 12 physics exam is tomorrow. She's been working through the exam review sheets that her teacher gave the class: forces, friction, gravity, relativity. The review sheets give the expected answers, so she can check her work. She asks for help when she can't figure out how to solve the problems, or when her solution doesn't match up with the provided answer.

I'm usually the one to help with homework, since I can speed-read tutorials to refresh my memory or dig into a new topic. Sometimes it's just a matter of nudging her towards one equation or another, or pointing out where she forgot to square a number or change a sign.

Sometimes we're both stumped, when my calculations show her math looks reasonable and I don't see why the answer should be different. This has happened a number of times in Physics. We've asked her to talk to her teacher and ask him to help her step-by-step, but she hasn't gone yet. Maybe she feels a little intimidated, or maybe lunch break is too crowded, or maybe he's hard to track down?

Fortunately, her physics teacher seems to be in the habit of reusing material posted online. When I search for the text of the question, I can sometimes find other people who have asked for help with the same problem, or a review sheet from a different school.

For example, we were getting stuck on a problem that started with “A fuzzy Velcro ball of mass 200 g strikes and sticks to a Velcro block (100 g)…” We solved it in a way that made sense to us, but our answer didn't agree with the one provided by her physics teacher. The only search result on Google was this sheet of practice questions. It didn't contain any solutions, though, so I nearly gave up there.

After making some headway on other problems, though, I thought I'd come back to that one and see if we could turn up additional resources. You can sometimes get to interesting places when you start playing around with URLs. The file's top-level domain https://rosedalephysics.wikispaces.com/ is a public wiki for Rosedale Heights School of the Arts. The exam review on the sidebar didn't match the exam practice document we were looking at, but a search through the Pages and Files section for June 2014 (which I picked up from the practice questions filename) turned up worked-out solutions. It confirmed that our answers and our methods were correct, and that the answer provided by J-‘s teacher was wrong. Maybe it was a typo, maybe he made a mistake, whatever. I can sympathize; I've made my share of mistakes as a teacher! Anyway, I'm glad J- asked for help and that we could clear up that mystery.

We should probably bring it to the attention of J-‘s teacher at some point. Incorrect review answers can lead to lots of frustration, second-guessing, and a lack of confidence. Maybe W- can mention it at the next parent-teacher interview, or J- can talk to her teacher after the exam. Anyway, I guess it's a good lesson in dealing with fallability, being resourceful, double-checking, and sometimes just trusting yourself anyway.

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