Normal Force

The normal force is the force exerted by a surface to support the weight of an object resting on it. It acts perpendicular to the surface and prevents the object from falling through the surface.

Key Points to Remember

1. The normal force is always perpendicular to the surface.
2. It is a contact force, meaning it only exists when the object is in contact with the surface.
3. The magnitude of the normal force is equal to the weight of the object when the object is at rest or moving at a constant velocity in the vertical direction.
4. The normal force can vary based on the angle of the surface and other factors affecting the contact between the object and the surface.

Examples of Normal Force

Some examples of the normal force in action include:

• A book resting on a table.
• A person standing on the ground.
• A car parked on a level road.

Study Guide Questions

1. What is the normal force?
2. When does the normal force act on an object?
3. What is the direction of the normal force?
4. How does the magnitude of the normal force change when an object is on an inclined surface?
5. Provide examples of the normal force in everyday situations.