Friday, 21 March 2014
Reporting the direction of a net or equilibrium force is quite the challenge for many of my kids because I require them to state the angle in standard position. Part of the problem, I know, is due to their geometry teachers teaching them the bearing system of measuring angles. For some reason, shifting the location of 0º and measuring CCW instead of clockwise just messes with these kids’ heads.
The other issue is not keeping it clear what the question is asking. Above, I ask students to find the direction of an equilibrium force. Without a good diagram, about 60% of my kids will screw it up about 80% of the time. Here’s a great example (look at #1).
For some reason, she thought that the equilibrium force would be 90º away from the net force, as she so eloquently explained in pencil on #1.
While we’re looking at it, check out how none of her diagrams include vector arrows showing direction. It keeps messing this one student up yet she won’t add the arrows to her drawings.