When you kick a ball, does it move forever or it slows down and stops?

Why does it slow down and stops?

When two surfaces touch each other or rub each other, like the ball and the ground. It

produces a force called friction

The friction causes the object to slow down.

What kind of force is formed between the shoes and the floor when you are walking?

Friction force

What kind of force is formed between the kids and the slide ?

Friction force

What kind of force is formed when you rub your hands?

Friction force

What kind of force is formed when you try to push any heavy object on the floor?

Friction force

Can you tell me where is the friction formed in the following

pictures :

What happens when there is water on the ground? Why?

Water reduces friction

What else reduces friction ?

Oil

Which is difficult to ride a bicycle on, the floor or the

sand?

Rough surface like sand, produces more friction.

Which is easier to ride a bicycle on, the floor or the grass

Smooth surfaces, produces less friction.

Rough surfaces

Smooth surfaces

Force that happens between objects that

touch each other.

1) Magnetism

2) Gravity

3) Friction

Which of these is a contact force?

Force that happens between objects without

touching each other.

1) Magnetism

2) Gravity

3) Friction

Which of these is a non-contact force?