Forces as Vectors
- Forces are vector quantities as they are described by both magnitude and direction
- The magnitude of a force is measured in Newtons
- The direction of a force can be described as left, right, up, down or even using angles
A free body diagram of an object with two forces acting on it
- The direction of a force can be imagined using a number line
- Numbers to the left of zero are negative as are forces pointing left
- Numbers to the right of zero are positive as are forces pointing right
Vectors represented as positive or negative vectors depending on their direction
- Not all forces are directed perfectly horizontally or vertically and thus need to have an angle described
- It is useful to describe an angle with respect to the vertical or the horizontal
A force of magnitude 100 N directed 40° to the horizontal