16 th Oct 09 Friction Learning Objectives To know what friction is. To know what friction is. To learn some uses for friction. To learn some uses for friction. Learn ways to reduce friction. Learn ways to reduce friction. Keywords: Friction

Starter Name all the forces you can think of; Name all the forces you can think of; forces

What is friction? Think pair share! Write a few examples

There is resistance to the rubbing motion. FRICTION The name of this resistant force is FRICTION Friction can Friction can;  Produce heatPeter  Wear things awayWatts  Slow things downSpent  Make a noiseMoney Rub your hands together for a minute. How does that feel? What causes the heat?

opposes motion  Friction always tries to slow moving objects down. It opposes motion.  It is a force between 2 touching objects.

Write down the numbers in your book for the missing words. 1. force 2. rough 3. smooth 4. surfaces Friction is a ___________________ caused by two __________________ moving over each other. ___________________ surfaces produce more friction than __________________ surfaces.

Friction can be a friend or a enemy at times.

Bear did not read the warning sign

You can not hold a pencil in your hand without friction. The pencil lead would not make a mark on the paper without friction. Writing

A pencil eraser uses friction to rub off mistakes written in pencil lead.

Your car would not start moving if it wasn't for the friction of the tyres against the street. With no friction, the tyres would just spin. Likewise, you could not stop without the friction of the brakes and the tyres. Driving car

When objects rub against each other, the surfaces are worn away. Friction with the ground causes the heels and soles of your shoes to wear away.

Cars have a brake system that uses friction between the rear tyres and the brake pads to slow down or stop the car.

FriendEnemy

Multiple choice Game Multiple choice Game What helps to reduce friction? What helps to reduce friction?friction? Adding o-- and g-----, this is called lubrication. Adding o-- and g-----, this is called lubrication.review

A unit of force is: A Newton B Metre C Gram D Kilogram

Which example shows unhelpful friction? A Friction between the tyre and the road. B Friction between the paper and the point of the pen. C Friction in the wheel axles of the bicycle. D Friction between your shoes and the floor.

Which of the following about friction is incorrect A Friction slows down a ball rolling in grass. B Friction wears away tyres. C Friction can speed up a falling object. D Friction makes objects hotter.

Which of these produce friction when they rub together A A rough surface and a smooth one. B 2 smooth surfaces. C 2 rough surfaces. D 2 smooth surfaces with oil between them.

Whic of the following is not an example of a lubricant? A Grease for bicycle chains. B Rubber on car tyres. C Water on swimming pool tiles. D Oil in car engines.

A force is a A A spring. B A movement. C An engine. D A push or a pull.

Friction is A A non contact Force. B A magnetic force. C A contact force. D Uses static electricity.

What is the frictional force that slows something down through the air? A Streamlining B Gravity C Thrust D Air resistance

Learning Outcomes Explain what friction is. State some useful applications for friction in everyday life. Name the ways to reduce friction.