New friction pp

Friction

What is friction?

Take an educational guess...

What do you think friction is?

Educational Guess✴Friction is a force that opposes motion.

✴Makes it difficult for an object to move across a surface

✴The action of one surface or object rubbing against another.

Friction is everywhere!

Friction is everywhere

Can you give me examples where I can find friction?

Let’s think about it!

Friction occurs every day in our daily lives

Examples of Friction

Humans being able to walk--we use friction to move!

Sitting in a chair and not slide off the chair--friction keep us sitting in our seats

We can keep our hands warm by ______??

Examples of Friction

We can keep our hands warm by RUBBING them together fast.

Let’s try this!!

Examples of Friction

Cars stop by using breaks--which use friction to stop the rotation of the wheels

Trains have steel wheels and run on steel tracks--which its weight and friction allows the wheel to turn

Car tires operate on the road--Why? Because of friction--tires rubbing the road creates friction.

Types of Friction?

Rolling friction

Static friction

Fluid friction

Sliding friction

Rolling Friction

The resistance between two surfaces

Example:

Tire rolled one way but the road was still

Static FrictionFriction is between two surfaces that are not moving past each other

Example:

When the balloon is rubbed on your hair...Static friction is created!

Fluid Friction

When an object is moving in liquid or gas

Example:

When you drink from a straw, the fluid inside the cup was forced to go through the straw...Why? Because GREATER FRICTION

Sliding Friction

The force that opposes the motion of two surfaces that past each other

Example:

When you go down the slide, you create sliding friction

Let’s look at a video!

http://www.youtube.com/watch?v=Zlhyw8fU1hI

Today’s Activity...We are predicting and testing an experiment!

Materials: toy cars, ramps, towels, masking tape, paper, pencils, stop watch (timer), and calculator.

The question is what are we going to do with these materials today?

Let’s think about!

Give up?

Let’s begin the race!!

After Activity...Review Game

Let's Review!