Friction notes 2 2
- 2. Daily Science 1. If a book is sitting on a desk would it be a balanced force or unbalanced force? Using arrows, show what forces are acting on the book. 2. How would you make the book become unbalanced if it’s balanced.
- 3. Scenarios What are the similarities between each scenario: • You sitting in a chair • Puck gliding across the rink • Brakes stopping a car • Football players colliding • Tires screeching across the pavement • Riding your bike • Surfing on some killer waves
- 4. What is friction? • Friction is a force that two surfaces exert on each other when they rub against each other. • What two factors do you think affect friction?
- 5. Two factors that affect friction. • The first factor is how hard the surfaces push together. • Ex. Rubbing your hands together, the harder you rub your hands the warmer they get. • The second factor is the types of surfaces involved. • Would you rather rub your face with sand paper or wax paper?
- 6. Types of Friction • There are four types of friction: 1. Static Friction 2. Sliding Friction 3. Rolling Friction 4. Fluid Friction
- 7. Static Friction • Static Friction is when friction is acting on objects that aren’t moving. • What could be some examples of this? • Example: desk not moving, standing still, pencil laying on desk. • The objects aren’t moving because of friction.
- 8. Sliding Friction • Sliding Friction occurs when two solid surfaces slide over each other. • How can this be useful? • Spreading sand on ice for more traction, using your brakes on your bike to stop. • How can this not be useful? • Slipping and falling on ice, falling off bike and skinning your knee.
- 9. Rolling Friction • Rolling friction is when objects roll across something. This provides rolling friction. • What are some examples of rolling friction? • Skateboard, rollerblades • What do scientist use to reduce the amount of friction in wheels? • They use ball bearings.
- 10. Fluid Friction • Fluid friction occurs when a solid object moves through a fluid. • Some types of fluids are water, air, and oil. • What are some examples of fluid friction? • Surfing • How is riding a bike an example of fluid friction. • A cyclists cuts through the air.