What is Normal Force?

Normal force is the force exerted by a surface to support the weight of an object resting on it. When an object is placed on a surface, the surface exerts an upward force to counteract the force of gravity pulling the object down. This upward force is known as the normal force.

Understanding Normal Force

When an object is at rest on a surface, the normal force is equal in magnitude and opposite in direction to the force of gravity acting on the object. This balancing act is what keeps the object from sinking into or falling through the surface.

Calculating Normal Force

The magnitude of the normal force can be calculated using the formula:

F_N = mg

Where F_N is the normal force, m is the mass of the object, and g is the acceleration due to gravity (9.81 m/s² on the surface of the Earth).

Study Guide

1. What is normal force and how does it relate to the weight of an object?
2. Explain the direction of the normal force when an object is at rest on a surface.
3. Discuss the relationship between the normal force, gravity, and the surface an object is resting on.
4. Calculate the normal force acting on an object with a mass of 10 kg resting on a horizontal surface.