Free-body diagram

Definition

A free-body diagram is a graphical illustration used to visualize the forces acting on an object. It simplifies complex systems into a single object with vectors representing all external forces.

5 Must Know Facts For Your Next Test

1. Free-body diagrams help in applying Newton's laws of motion by isolating an object and identifying all forces acting upon it.
2. The length and direction of the arrows in a free-body diagram represent the magnitude and direction of the respective forces.
3. Common forces shown include gravitational force, normal force, frictional force, tension, and applied forces.
4. To solve for unknowns using a free-body diagram, set up equations based on Newton's second law: $\sum F = ma$.
5. It is crucial to choose an appropriate coordinate system to simplify the analysis of forces.

Review Questions

• What are two common types of forces often depicted in a free-body diagram?
• How does Newton's second law relate to solving problems using free-body diagrams?
• Why is choosing an appropriate coordinate system important when creating a free-body diagram?

Related terms

Newton's First Law:

An object will remain at rest or in uniform motion unless acted upon by a net external force.

Normal Force:

The perpendicular contact force exerted by a surface on an object.

Frictional Force: The resistive force that opposes the relative motion or tendency of such motion of two surfaces in contact.