4.8 Resultant Forces & Free Body Diagrams

Question 1

What are free body diagrams?

Answer 1

Simple diagrams that show all of the forces that are acting on a particular object. We do this using force arrows.

Question 2

In free body diagrams, what do the sizes of the arrows show?

Answer 2

The relative magnitudes of the forces

Question 3

In free body diagrams, what do the directions of the arrows show?

Answer 3

The directions of the forces acting on the object

Question 4

What is the resultant force?

Answer 4

A single force that takes into account the sizes and directions of all of the forces

Question 5

If the forces all act along the same line (they’re all parallel), how is the overall effect found?

Answer 5

By adding those going in the same direction and subtracting any going in the opposite direction.

Question 6

If you have two forces that are perpendicular to each other, how can the resultant force be found?

Answer 6

Using scale drawings

Question 7

What does it mean for an object to be in equilibrium?

Answer 7

The two forces being equal in size and act in opposite directions. The forces are balanced and cause a zero resultant force.