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What is Friction ( contact force ). Force that acts when two objects rub (contact) each other Friction comes from solid, air or water http://phet.colorado.edu/sims/friction/friction_en.html ( Let us visit this website). How does Friction affects motion?. Friction opposes movement.
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1. What is Friction ( contact force ) Force that acts when two objects rub (contact) each other
Friction comes from solid, air or water
http://phet.colorado.edu/sims/friction/friction_en.html ( Let us visit this website)
2. How does Friction affects motion? Friction opposes movement
3. How does Friction affects motion? Slows down
4. How does Friction affects motion? Getting moving
5. How does Friction affects motion? Getting moving
6. How does Friction affects motion? Grip or stop
7. Factors affecting friction ( surface)http://www.bbc.co.uk/schools/scienceclips/ages/8_9/friction.shtml ( visit this website) Smooth surface Rough surface Lesser bump and hollows means lesser friction
can move the object continuously with little force. More bump and hollows means more friction
Can move the object slowly with greater force
8. Smooth surface The smoother the surface the faster the object glides with little force
9. Rough surface Objects will move slowly with greater force on the rough surface.
10. Factors affecting friction Air Resistance Example: Is the force that provide a backward force
Size and shape are the factors that affect air resistance. ( the bigger the size and shape the more is the air resistance)
http://www.youtube.com/watch?v=oTMLXBeQ40E
http://www.youtube.com/watch?NR=1&v=ur40O6nQHsw
11. Friction: Good and Bad Good Bad Hold objects
Stops object
Able to play ,run ,walk etc
Gives energy
Shoes, slippers , tires and anything that are used for moving are worn out.
Machine become less efficient
Reduce speed
Cause accidents
Cause sparks
12. Ways of reducing friction Applying wax or polishing
Use rotating objects
Streamlining
New design shoes for the athletes