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Learning Objectives
You will be able to state the effects of friction
You will be able to Describe different factors that affect friction
You will be able to suggest ways to reduce friction.
Keywords
FrictionLubricationDrag force
Streamlined
There is resistance to the rubbing motion. The name of this resistant force is FRICTION
Friction can;Produce heat Peter
Wear things away Watts
Slow things down Spent
Make a noise Money
Rub your hands together for a minute. How does that feel?
What causes the heat?
Friction always tries to slow moving objects down. It opposes motion.
It is a force between 2 touching objects.
Learning Objectives
You will be able to state the effects of friction
You will be able to describe factors that affect friction
You will be able to suggest ways to reduce friction.
Keywords
FrictionLubricationDrag force
Streamlined
Investigating Friction
• You can use newton meters to investigate the effect of friction.
Equipment around the room • Newton meter• 6 x 100 g masses• wooden blocks• different surfacesSafety• Do not overload the springs on newton meters.
Investigating friction
The type of graph you plot will depend on the variables you used.• When would you plot a bar chart?• When would you plot a line graph?
How does the roughness of the surface affect friction?
Learning Objectives
You will be able to state the effects of friction
You will be able to describe factors that affect friction
You will be able to suggest ways to reduce friction.
Keywords
FrictionLubricationDrag force
Streamlined
What helps to reduce friction?
• Adding o-- and g-----, this is called lubrication.
• Can you think of where this would be used?
Learning Objectives
You will be able to state the effects of friction
You will be able to describe factors that affect friction
You will be able to suggest ways to reduce friction.
Keywords
FrictionLubricationDrag force
Streamlined
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.
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