A contact force is a push or pull that is exerted when two or more objects are physically touching. There are several types of contact forces.
- An applied force, where a person or object is pushed or pulled by another object, is one type of contact force.
- Friction, which is a force exerted on a moving object and opposes the motion of that object, is a contact force.
- When a contact force acts perpendicular to an object, it is called a normal force. A normal force holds a book on a table.
Of these types of forces, the normal force might be the least familiar to you, but it is everywhere. When you sit on a chair, the chair is holding you up with normal force. Your computer is being held there by the normal force exerted by the table. If you lean against a wall, the wall exerts a normal force on you. If you are building something and are holding a piece of wood in place, you are exerting a normal force on the wood. Your building partner might be exerting an applied force on the nail with a hammer.
Friction is the force that slows a ball down as it rolls across the gymnasium floor.
An applied force is the force of you pushing a door open.
Contact Forces
What is a contact force?
Drag the actions onto the correct forces present in the picture above.
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The baby sitting in the stroller
the woman pushing
on the ground the woman pushing the stroller
The stroller wheels
against the ground |
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