Renovating My Classroom

Last week, for the first time that I can remember in my career as a teacher, I hit the wall.  It was epic.  One minute I’m saving my students from illiteracy and then WHAM – I hit the wall like Wile E Coyote.  In reality, I was teaching an English 12 student how to write an academic essay and she got stuck and couldn’t seem to get unstuck.  And then I got stuck.  I tried pretty much everything I knew how to do to help her understand and nothing seemed to help.  I felt like a vehicle stuck in deep mud or snow and no matter how much you push down on the gas, the tires just keep spinning – going nowhere.  And it wasn’t like I was dealing with a disengaged, couldn’t-care-less-about-school student.  She’s bright and highly motivated.  What kind of teacher can’t teach an engaged, smart, highly motivated student?  Hi. …

Free-body diagrams are a pretty useful tool and I wanted to devote a little time to talking about the ones I created for the Danny Macaskill video.  In particular look at the short clip starting at 50 seconds:

I had originally thought he pushed down with his hands and feet but in viewing the video I see I was wrong.  What he does is pull the front wheel up, then push himself up with his feet.  I realized this when I was doing a video analysis, which I’ll post in a bit.

To create the free-body diagram (FBD) I made a few assumptions and simplifications.  I ignored all horizontal forces and just focused on vertical forces.  I also assumed the rider and bike have similar masses and therefore similar weights.  I don’t have numbers, but if the bike was too much heavier than him it would be hard to pull…