Question

What is the meaning of frictional force I will give you 10 points pls don't spam ​

Answer 1

$\LARGE{\underline{\sf{\blue{Frictional \: Force :}}}}$

An external force which oppose a relative motion between 2 surfaces when they are is in contact.

$\LARGE{\underline{\sf{\red{EXTRA \: INFORMATION :}}}}$

- There are four type of friction

1-$\small{\underline{\sf{\purple{ static \: Friction :}}}}$

2-$\small{\underline{\sf{\purple{ rolling \: Friction :}}}}$

3-$\small{\underline{\sf{\purple{ sliding \: Friction :}}}}$

4-$\small{\underline{\sf{\purple{ fluid \: Friction :}}}}$

- First three friction occurs between solid surfaces while the fourth one occurs only in fluid which may be gas or liquid

Answer 2

Frictional force :- When we push a box lying on the floor with a small amount of force, it does not move at all. It means that the surface of the floor, on which the box is resting, exerts some forces on the box which act in a direction that is opposite to the force of our push. This natural force between the floor and the bottom of the box which opposes the motion of box on the floor is called friction. The force acting on the two surfaces in contact which opposes the motion of one body over the other is the force of friction.

About frictional force :-

• Frictional force is a contact force.

• Friction always act in the opposite direction to the motion of the body.

• If you stop pedalling your bicycle on a level road, you observe that its speed decreases gradually. This is due to friction.

• Friction depends on roughness or smoothness of the surface.

• The friction is directly proportional to the roughness of the surface.

• Friction is more if the surface is rough.

• Friction is less if the surface is smooth.

Factors affecting friction are :-

1. Nature of surface: If there is more roughness, more is the friction. if the surface of an object is smooth, less friction is produced.

For example, a ball rolls slowly and covers a lesser distance on a rough surface such as muddy playground.

And , obviously it means that to get the ball rolling, we have to apply a force which is greater than the frictional force offered by the ground.

This also explains why we cannot hold a glass with oily hands. Our hands are greasy and smooth and we know that a smooth surface offers lesser interaction with the glass. And hence, it tends to slip.

Another example of this is that while trekking on hilly and watery terrains, we wear groovy sports shoes so that rough shoes establish better locking with the hilly trains, increase friction, provide more grip and decrease chances of a slip$.$