1. Vectors have both magnitude and direction, while scalars only have magnitude. 2. Common vector quantities include velocity and force, while common scalars include mass and time. 3. Vectors can be represented by arrows in diagrams or with signs to indicate direction in equations. The resultant vector represents the total effect of multiple vectors.

1. Topic 1 – Physical Measurement 1.3 – Vectors and Scalars

2. Vectors and Scalars In Physics some quantities have values that depend on direction and some do not.

3. A quantity that has a direction associated with it is called a vector. Example velocity. A quantity that has no direction is called a scalar. Example mass For a vector quantity a “+” or “-” sign shows direction

4. For a scalar quantity a “-” sign is (usually) meaningless

5. Vectors and Scalars Sort the list of quantities below into a table of vectors and scalars. Mass Displacement

6. Time Energy

7. Velocity Speed

8. Distance Acceleration

9. Amount of Substance Force

10. Representing Vectors A vector is generally represented in equations by using an underline, or by an over-arrow. Some textbooks use bold fonts to show vectors.

11. Example:

12. Representing Vectors Vectors are represented in diagrams by an arrow (often drawn to a scale) pointing in the correct direction but attached by its tail to the point at which it acts. Example W=45N F=20N

13. Combining Vectors Often in Physics we need to find what the total effect of a group of vectors is.