Forces have a magnitude (strength) and a direction. Forces can be represented as arrows with the length of the arrow representing the magnitude of the force and the head of the arrow pointing in the direction of the force. Using such arrows, the resulting force (net force) and direction can be determined.
Forces Can Be Represented Using Vectors
- Vectors are arrows.
- Forces have a magnitude (strength) and a direction.
- Forces can be represented as arrows (vectors) with the length of the arrow representing the magnitude of the force and the top of the arrow pointing in the direction of the force.
- Using these arrows, the resulting force (net force) and direction can be determined on an object.
Free Body DiagramsFree-body diagrams are diagrams used to show the relative magnitude and direction of all forces acting upon an object in a given situation. These diagrams will be used throughout this entire forces unit.
|
Net Force Equals the Resulting Force
A resultant force, also called a net force, is the sum (total) of all forces applied to an object.
If there is no net force acting on the object, the motion does not change.
|
If there is a net force acting on an object, the speed of the object will change in the direction of the net force.
|
Calculating Net Forces
When to Add Forces |
When to Subtract Forces |
When forces act in the same direction, their forces are added.
|
When forces act in opposite directions, their forces are subtracted from each other.
|
Video Guide:
|
|
Topic Tips
- Forces can be represented as arrows with the length of the arrow representing the magnitude of the force and the head of the arrow pointing in the direction of the force.
- Using such arrows, the resulting force (net force) and direction can be determined.
- When forces act in opposite directions, their forces are subtracted from each other.
- When forces act in the same direction, their forces are added.