Friction Definition
Friction is a force that resists the relative motion between two surfaces that are in contact.
When two things rub together, friction is what makes it hard to slide them apart. It is why we can walk without slipping. Our shoes grip the ground because of friction.
If we try to push a heavy box, friction is what makes it tough. The rougher the surfaces, the more friction there is. But, if the surfaces are smooth, like ice, there’s less friction, and things can slide easily.
Types of Friction
Friction can be categorized in various types, based on different criteria such as the nature of the surfaces in contact. There are four types of friction. Let’s discuss them below.
|
Type of Friction |
Description |
Example |
|---|---|---|
|
Static Friction |
The force that needs to be overcome to start moving an object. It acts when objects are not moving relative to each other. |
Pushing a couch that doesn’t immediately start moving. |
|
Kinetic Friction |
Occurs between surfaces in relative motion. It’s usually less than static friction. |
Sliding a book across a table. |
|
The resistance encountered by an object rolling over a surface. It’s typically less than sliding friction. |
A bowling ball rolling down a lane. |
|
|
Resistance faced by objects moving through a fluid (liquid or gas). |
Swimming in water or a leaf falling through the air. |
Methods to Reduce Friction
Friction is a force that opposes the motion of an object when it is in contact with another surface. It arises from the interactions between the atoms and molecules on the surfaces that are in contact. In this article, we will learn about friction and different methods to reduce the fraction.