1. Multiplying Vectors - Dot and Cross Products -
13.3

2. Dot Products… One of two ways to multiply vectors
Yields a number – not another vector
Basic Defintion:

3. a b q What is it good for? Angles between vectors Direction cosines
13.3: 21, 23, 25
Direction cosines
13.3: VPython demo
Projection vectors
13.3: 35, 47 a q b

4. Cross Products… A way to multiply two vectors and return a new vector
Basic Definition:
How do you remember this!!!
a X b b
VPython demo a

5. What’s it good for? Cool way to create normal (perpendicular) vectors
Used in many basic definitions in physics:
Examples: 13.4: 4, 13,33