**Chapter 3** is about vectors.

pages 30 and 30b introduce vectors and vector addition.

The Chapter 3 Review Sheet should be started now.

On pages 31, 32, and 33 we investigate forces. Simple harmonic motion is first introduced in the lab exercises on page 33.

On page 31R we review some important fundamental facts about triangles.

On pages 34 and 34R we figure out how to describe the direction of a vector clearly, we learn more about vector addition, and review it all on 34R.

On pages 35 and 36 we clarify the relation of weight, mass, and gravity. Page 36 is a lab exercise to analyze the forces acting on a cart on an inclined plane.

pages 37 and 38 are about friction. First we think about the forces acting on a coasting object, then on p. 38 we investigate the relation between friction and normal force.

On pages 39 and 39c we continue investigating the relation between friction and normal force, and we define "friction coefficient". Page 39c is about the use of graphing calculators in the friction experiment.

pages 40 and 40b contain a bunch of practice exercises involving friction.

November Test with skill sheet and solutions: