Static and Kinetic Friction

​Types of Friction

Four Types

There are four types of friction:

1. Static

2. Sliding

3. Rolling

4. Fluid

Multiple Choice

Which of these is NOT a type of friction?

• static

• scraping

• rolling

• sliding

Static Friction

• Friction that happens when you TRY to move an object on a surface. It is between something that is sitting still and the surface its on.

• Think of a book lying on top of a desk.

  • Static friction keeps the book from falling off, even if the desk isn't totally straight/flat.

Multiple Choice

Static friction is friction between something that is sitting still and:

• the surface it's on

• something completely flat

• a moving part

• itself

Sliding Friction

• Friction between two things as they slide against each.

• Think of going down a slide or sliding an object across the floor.

Multiple Select

Check all of the examples of sliding friction.

• a pencil sitting on a desk

• ice skating

• using a playground slide

• sliding a book across the table

Rolling Friction

• When a wheel or ball rolls over a surface.

• Examples: a truck tire, a bicycle tire, a soccer ball, a bowling ball.

• Can be affected by how rough or smooth the material is that it rolls over.

Dropdown

True or false? A tire using rolling friction is affected by how rough or smooth the surface the tire is rolling on.​

Select answer

Fluid Friction

• Friction caused by air.

• Example: It slows down the motion of an airplane flying in the air.

​Air Resistance

• Friction caused by water.

• Example: The water in a swimming pool "resists" you when you swim against it.

Water Resistance

Multiple Select

Select all that are correct. Fluid friction is:

• air resistance

• static friction

• water resistance

• sliding friction

Let's Quiz Ourselves!

Multiple Choice

What kind of friction: A lamp sitting on a table.

• static

• sliding

• rolling

• fluid

Multiple Choice

What kind of friction: Sliding a block across the floor.

• static

• sliding

• rolling

• fluid

Dropdown

What kind of friction: Rolling a log on the ground. ​

Select answer

Multiple Choice

What kind of friction: Two pieces of paper rubbing against each other.

• static

• sliding

• rolling

• fluid

Drag and Drop

What kind of friction: Paper sitting on a tabletop.

Placeholder

Drag these tiles and drop them in the correct blank above

static

sliding

rolling

fluid

Dropdown

What kind of friction: Wheels on a moving car.

Select answer

Multiple Choice

What kind of friction: Swimming.

• static

• sliding

• rolling

• fluid

Multiple Choice

What kind of friction: sailboat trying to sail against the wind.

• static

• sliding

• rolling

• fluid