What is Friction?

Friction is the force that resists motion when one object rubs against another. When two objects rub against each other, friction is generated. The force of friction acts against the motion and acts in the opposite direction.

Friction and Energy

When one object slides over another, it begins to slow down due to friction. This means it loses energy. However, the energy does not disappear. It converts kinetic energy (also called kinetic energy) to thermal energy. That’s why we rub our hands when it’s cold. By rubbing them, we create friction and thus heat.

Preventing Friction

In some cases, we want to avoid friction for easier movement. A good example of this is a ball or wheel. They roll to help reduce friction. Another way to reduce friction is to use a lubricant such as grease or oil. Machines and engines use grease and oils to reduce friction and wear so they can last longer.

Another way to reduce friction is to vary the types of materials in contact with each other. For example, the contact of tape with steel will create less friction than rubber on concrete. That’s why skates slide so easily on the ice, but you don’t slip when wearing rubber shoes on the sidewalk. These different materials are said to have different “coefficients of friction”.

Using Friction

Friction is also a great help for us. After all, we would all slide around without friction to keep us steady. Friction is used in car brakes, when we walk or climb slopes, set fires, ski down hills, etc.

Experiment with Friction

Different types of surfaces create different amounts of friction. Some materials are much finer than others. Take three flat objects with different surface types. Place them on one end of the tray and lift them up slowly. The object with the least friction will begin to slide first.

There are two main factors that will affect the total amount of friction: 1) the roughness of the surface (or “coefficient of friction”) and 2) the force between the two objects. In this example, the weight of the object combined with the angle of the pan will change the force between the two objects. Play with different objects and see how these two factors change the force of friction.

Types of Friction:

Dry Friction – This is what we are mainly talking about here. Dry friction occurs when two solid objects touch each other. If they are not moving, it is called static friction. If they move, it is called dynamic or sliding friction.

Fluid Friction – Fluid friction involves liquid or air. The resistance of the air on the plane or the resistance of the water on the boat is the frictional force of the fluid.

Rolling Friction – Rolling friction occurs when a circular surface rolls over a surface, such as a ball or wheel.

Interesting facts about Friction

While wheels are great for rolling and reducing friction, they cannot function without friction.

It would be difficult to stand without friction.

Friction can create static electricity.

The more two surfaces are pressed against each other, the more force is required to overcome the force of friction and cause them to slide.

Fluid friction is used a lot in water parks so that we can slide smoothly and quickly down giant slides.