Friction
Friction: a force that opposes motion between two surfaces that are in contact. Friction can cause a moving object to slow down and eventually stop.
When a force is applied to an object but does not cause the object to move. Static means “not moving” Contrasting examples…walking on asphalt and walking on ice Static Friction
Kinetic Friction The friction between 2 moving surfaces There are 2 main types: Sliding friction Rolling friction Kinetic Friction
Sliding Friction (kinetic friction) Force of sliding friction is usually greater than the force of rolling friction. Example…ever tried to slide really large and heavy objects? Sliding Friction (kinetic friction)
Rolling (Kinetic Friction) The force of rolling friction is smaller than sliding friction. If you put that large heavy object on wheels it be much easier to move! Rolling (Kinetic Friction)
This includes air resistance as well as resistance in a liquid Example…sky diving and swimming in a pool Fluid Friction
Brakes in cars work by pressing pads together within the car’s wheel assembly. This resistance to the motion off the car results from which of the types of friction? Sliding friction Friction Review
The force of friction between a rock and the ground just before the rock starts to slide down a mountain slide. Static friction, sliding friction, rolling friction or air resistance
The force of friction between a bike tire and the road as a cyclist skids to a stop Static friction, sliding friction, rolling friction or air resistance
The force of friction that slows down a skier if she doesn’t wax the bottom of her skis. Static friction, sliding friction, rolling friction or air resistance
The type of friction that you would want to increase if you were trying to walk across a large sheet of slick ice. Static friction, sliding friction, rolling friction or air resistance
Put the different types of friction in order of strongest force to weakest force. Static friction is strongest, followed by sliding friction, and then rolling friction, which is weakest. Friction Review
The type of friction that athletes often try to reduce by wearing tight fitting outfits during races. Static friction, sliding friction, rolling friction or air resistance
What is the force of friction between a rock and the ground just before the rock starts to slide down a mountain slide? What is the force of friction between a bike tire and the road as a cyclist skids to a stop? What is the force of friction that slows down a skier if she doesn’t wax the bottom of her skies?
What is the type of friction that you would want to increase if you were trying to walk across a large sheet of slick ice? What is the type of friction that athletes often try to reduce by wearing tight fitting outfits during races?