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Write the type of KINETIC FRICTION SHOWN BELOW. . What do you know about friction?. Friction: A Force That Opposes Motion. TASK. Follow along as we review the answers to the friction questions. ANSWER THE QUESTIONS ON THE PAPER THAT WAS PASSED OUT TO YOU.
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What do you know about friction? Friction: A Force That Opposes Motion
TASK • Follow along as we review the answers to the friction questions. • ANSWER THE QUESTIONS ON THE PAPER THAT WAS PASSED OUT TO YOU.
In your own words, write a definition for the term friction. • Friction is a force between any two surfaces, that opposes motion.
Which direction is the force of friction pushing against the block?
Why is it easier to slip when there is water on the floor? • The water is a lubricant that when spilled, fills in the hills and valleys on the floor and reduces friction between your feet and the floor
Explain why friction occurs. • Friction occurs because surfaces are covered with microscopic “hills and valleys” that stick to each other when they come in contact.
Friction is caused when microscopic hills and valleys of objects rub together:
How does the roughness of surfaces that are touching affect the friction between surfaces? • Rough Surfaces have more hills and valleys that increase the force of friction. Smooth surfaces have less hills and valleys, therefore less friction occurs.
Which will have more friction? These surfaces will have more friction because they have larger hills and valleys than the other picture. This means they are more rough.
Describe how the amount of force pushing two surfaces together affects friction. • If the force pushing the two surfaces together is great, the hills and valleys are in closer contact and friction increases.
Name two ways in which friction can be increased. • Make a surface rougher • Push surfaces together harder
List the two types of friction, and give an example of each. • Kinetic- sliding a book across the tabletop • Static- pushing a piece of furniture and it not moving.
On the back of your paper: • List the three types of Kinetic Friction that we have spoken about and give an example of each.
Three types of Kinetic Friction: • Sliding Kinetic Friction- moving a book across a desk, applying brakes in a car, scratching your arm • Rolling Kinetic Friction- wheels of a bike, toy car, trains on a track • Fluid Kinetic Friction- oil lubricating parts on a plane, car, or bike, water flowing through a hose