Finding the Resultant Force (GCSE Physics)

Finding the Resultant Force

Force Diagrams

Forces as Vectors

• Forces have magnitude and direction. As we discussed previously, forces can be represented as arrows. The length of the arrow is the size of the force, and the direction of the arrow will be the direction of the force (up, down, forwards or backwards).

Drawing Force Diagrams

• More than one force can act on an an object. To find the overall force on an object, you must consider all of the individual forces. For example, friction which is a force that opposes motion.
• Label all the forces on a diagram. Labelling all of the forces will help you to see if any of the forces cancel out. This will happen when two arrows are parallel, but point in opposite directions.

Finding the Resultant Force

• You can find the resultant force. The resultant force will be the ‘overall force’, which is the sum of all forces present. When you work out resultant forces, you will need to find the horizontal (forward / backward) force, and the vertical (upwards / downwards) force.
• If all the forces are balanced, then the resultant force will be zero. If forces are equal and in opposite direction, there is a resultant force of zero. All the individual forces will cancel each other out. The object is said to be in equilibrium at this point.