Teaching Angles - Use Your Arms

Most recently, I was working with a student on the angles in a triangle. We started with a circle to show the angles all the way around, their sizes, and how they compare to each other. Then, I set my arms hand to elbow in an L shape. We worked on showing the sizes of various angles by moving my hand at 12-o'clock (90 degrees) to a position that would show the angle size when my other arm was at 9-o'clock (zero degrees). It worked very well.

8/15/2013 | Cynthia O. | 1 comment

Comments

I military when they wanted to give a command for moving in a certain direction. The standing direction always indicates to be the big arm of a clock, and every hour ( o'clock) indicate 30 degree. i.e. 1 o'clock the 2 arms make 30 degree, 2 o'clock the 2 arms make 2*30 = 60 degree and so on.

So, commands for moving in a certain direction are given in the direction of 1 clock, 2 O'clock, .... , meaning move angles of 30, 60, ... always take the standing direction is always indicate the direction of big arm of the clock.

And definition of Azimuth is given by angle made between a direction and North pole, in clockwise direction. In military, they make the big arm of a clock, to be Magnetic North.

9/11/2013 | Parviz F.