10 Examples of Rolling Friction

In physics, friction is a force acting between two bodies at a point of contact when they are in relative motion. Friction can be classified into two types based on the mode of contact, sliding friction and rolling friction. Rolling friction comes into the picture when an object rolls over the other. For example, a football rolls over a surface, whereas a wooden box slides over the surface. In this article, we look at 10 examples of rolling friction in our everyday lives.

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Anything that rolls over a surface has rolling friction involved between the surface and the object at the point of contact. The rolling friction will behave in a manner similar to normal sliding friction. The friction will act in the plane of contact and opposite to the direction of force applied. The major advantage of using rolling friction is that it offers less friction compared to sliding friction. So, wherever there is a necessity of reducing friction, rolling friction can be used.

10 Examples of rolling friction

Wheels of vehicles
Soccer Ball
Wheels of trains
Wheels of skateboard
Trolley bag
Driving on a wet floor
Stopping a rolling ball
Thin tires of vehicles
Zorbing
Rolling of a pen without a cap

Examples of rolling friction

Wheels of vehicles: The wheels of vehicles are round so as to allow rolling friction rather than sliding friction. Imagine a car with square wheels, how much force will be required to overcome friction? Remember rolling friction is always less compared to sliding friction. Rubber tires on wheels are preferred because it offers more grip on the surface. Plus, the road is made with concrete or tar to reduce rolling friction.

Example of rolling friction: Wheelbarrow Image by Manfred Richter from Pixabay

SoccerBall: A soccer ball is particularly round because it has to move freely. The rolling friction will be less as compared to a square or irregularly shaped ball. The rolling friction is dependant on the shape of the object.

Wheels of Trains: The wheels are round and made up of metal to ensure the least rolling friction with the metallic rails.

Wheels of skateboard: The wheels of skateboards are kept small in diameter to reduce friction. As friction is directly proportional to the mass of the object.

Example of rolling friction: Wheels of skateboard
Image by Luisella Planeta Leoni from Pixabay

Trolley bag: Instead of pulling a bag along the floor, the addition of wheels will make it easy to pull the bags.

Driving on a wet floor: It is very difficult to drive a vehicle on a wet floor. The coefficient of rolling friction will be very low on such surfaces, and we can easily lose control of the vehicle.

Stopping of a cricket ball: A cricket ball comes to a halt in a grassy field due to the friction of the ball with the grass.

Thin tires of vehicles: Small vehicles like bicycles have thin tires rather than broad one to reduce rolling friction.

Zorbing: In this adventure sport, you experience thrills due to the rolling friction of the ball with the surface. If there was no friction the ball would be rolling infinitely.

Examples of rolling friction: Zorbing Image by PanchoOn from Pixabay

A pen with a blunt cap: A pen kept on a desk will roll over and fall down. A slight protrusion is often made in the cap to stop it’s rolling over.

What are the most common examples of rolling friction in our everyday life?

The most common examples of rolling friction would be riding on cycles or any vehicle with round wheels. Other examples include sports like soccer, skating, basketball, etc.

How can we reduce/increase rolling friction?

The smoothness of the object: Irregularities on the surface hold the key to rolling friction. More the irregularities more will be friction. The smoother the surface, the lesser the value of rolling friction.
The shape of the object: A perfectly round object will have less friction compared to irregularly shaped ones.
Elastic deformation of the material: Materials like metals have very little elastic deformation and, hence have very little resistive force. However materials like rubber offer more resistance due to higher elastic deformations.
Load of the object: Friction is always directly proportional to the mass of the object.

Examples where rolling friction is chosen over sliding friction

Rooling friction and sliding friction — Does wheels reduce friction?

Transportation: In any motion or any kind of transportation, wheels are used to reduce friction. Examples would include trolley bags, vehicles, skateboards, etc. Sliding friction will make it very hard to travel.

Sports: Most sports make use of rolling friction like cricket, soccer, baseball, etc. Very few sports like curling, carrom are based on sliding friction.

Friction reduction: Ball bearings and rollers are used between machine parts to reduce friction between two sliding parts. This will improve the efficiency of the machine.

Reducing wear and tear/heating effects: We tend to roll on the floor rather than slide. You must have noticed this many sporting events, that the athletes roll after a dive so as to avoid any injuries. This is because the resistance by the ground when we roll is less compared to when we slide.