Teacher resources and professional development across the curriculum

Teacher professional development and classroom resources across the curriculum

 A B C

Notes for Session 8, Part B

 Note 3 If you are working in a group, you may want to start by actually doing the "mirror trick" described here. When you calculate, remember that you should use a number closer to the height of your eyes rather than your actual height, but position yourself so that you just see the top of the other person's head. For Problem B1, you can ask others to figure out your height based on the setup used and the other person's (now known) height.

 Note 4 If you are working in a group, compare the triangles you made with the triangles other people made and discuss what you notice.

 Note 5 The mirror acts like there's an exact copy of the world directly behind it that you are peeking into. If you connect your eyes to the top of the other person's head, as if the line went through the mirror, the angles would be the same because they are vertical angles. So the reflected angles are the same as the "behind-the-mirror angles," which are the same as the angles at which you are looking.

 Note 6 If you're working in a group, have each participant create just one triangle for each part, and then compare the results as a group.