Drawing Force Diagrams
Draw forces acting on one object as labelled arrows. Arrow length shows relative force size and arrow direction shows force direction. For two forces along one line, equal and opposite forces balance. Combine forces to find the resultant, which changes motion when it is not zero. Draw the resultant separately from the individual forces.
What a learner can do afterwards
- Draw a force diagram with labelled arrows showing direction and relative size for at least two forces acting on an object
- Use their diagram to explain whether forces are balanced or unbalanced and what will happen to the object
- Add a resultant force arrow to a diagram and explain how they calculated it
1 · Read
Choose one object. A force diagram shows the pushes and pulls acting on that object. Draw one arrow for each force and label it. A longer arrow means a stronger force. The arrow points the way the force acts. Use the same scale for every arrow.
A book rests on a table. Gravity pulls down and the table pushes up equally. Draw matching arrows in opposite directions. These forces are balanced. Balanced forces do not change motion: a still object stays still, and a moving object keeps the same speed and direction.
The resultant is the combined push or pull. Along one line, add forces pointing the same way. Subtract opposite totals; the larger total gives the direction. Equal opposite forces cancel, even if another force acts too. Draw the resultant separately, not as another force on the object. A rightward resultant can speed up a box moving right or slow a box moving left.
Check every arrow's label, direction and length. Two equal arrows balance only if they point opposite ways. A force diagram tells you how motion changes, not always which way the object is already moving.
Label each force arrow. Its length shows strength and its direction shows the force direction. Combine the forces to find the resultant.
Readings and flashcards written for this dataset.
2 · Watch
Take it off screen
Where it sits
Where this leads
Jobs that lean on this skill. Follow one to see everything it is built on.
8 questions wait behind this lesson, each with its answer explained. Every answer feeds the sky: stars light as they are learned, and dim when it is time to come back.