Vector Quantities

A quantity that doesn’t involve direction is a scalar quantity. These include such things as distance, time and speed

A quantity that does involve direction is a vector quantity. These include such things as position, displacement, velocity and acceleration

Displacement is the distance an direction traveled between the beginning and end of a trip. If we represent displacement on a number line then, 0 is the reference point. The positive numbers are one direction, usually forward or north or east and the negative numbers are the opposite direction, backward or south or west.

Displacement

If my lab is the reference point in the school, identify the displacement for the following places:◦ The gym◦ The IA shop◦ The elementary school

Another way to show vector quantities is to draw a line segment showing direction and size. This is called a vector. A vector must include size, units and a direction in a square bracket; for example 57m [N]. A vector quantity is represented by a symbol that has a small arrow over it,

Drawing Vectors

Choose a reference point Decide on an appropriate scale and write it

down. For example, 1cm=10km Draw a line to the stated scale, and write

the size of the vecotr next to the line State the direction – usually N,E,W or S as a

reference Add an arrow pointing in the direction of the

vector

Follow these rules when drawing a vector:

Using the correct displacement symbols and references identify the location of 3 different items in the classroom based on ________’s desk as a reference point.

Actvity: