Chapter 3 Two-Dimensional Motion and Vectors

3.1 Introduction to Vectors

Definitions

Scalars and Vectors

Vectors indicate direction; scalars do not Examples of scalars: time, speed,

volume, temperature Examples of vectors: displacement,

velocity, and acceleration

Vectors are represented by symbols With bold letters or with an

arrow above the symbol

With diagrams▪ Arrows pointing in the direction

the of vector and length related to magnitude.

Vectors can be added graphically Must be in same units Adding gives a quantity called the resultant. Steps for Adding Vectors Graphically:

1. Draw vectors to scale in the correct direction and place them head-to-tail

2. Then draw a straight line from tail of first vector to head of last. This is the resultant.

3. Measure the length of the resultant and use scale to estimate/convert this measurement to the actual magnitude.

4. Use a protractor to measure the angle between the first vector and the resultant.

Properties of Vectors

Vectors can be moved parallel to themselves in a diagram

Vectors can be added in any order.

To subtract a vector, add its opposite

Multiplying or dividing vectors by scalars results in vectors