Physics 5
Sliding friction, or parallel
Kinetic friction is sometimes called?
Constant
Kinetic friction remained ____ regardless of the force applied
Coefficient of kinetic friction
Needed to calculate the force of kinetic friction
Components
Projectinos of a vector parallel to the x axis and another parallel to the y axis
Increases
Static friction _____ with the force applied until it reaches a maximum value
Kinetic and static
Two types of friction
Equilibrant
Force that puts an object into equilibrium
Coefficient of static friction
A dimensionless constant depending on the two surfaces in contact. It is used to calculate the maximum static frictional force that needs to be overcome before motion begins
Static friction
Depends on the normal force exerted by an object when there is no motion between the two surfaces
True!!!
Does force of friction depend on normal force between two objects? The harder one object is pushed against the other, the greater the force of friction that results?
Nooooo not at all
Does the force of friction depend on the surface area in contact or the speed at which the objects move past each other?
From tip to tail
How are vectors connected?
The static friction will match the applied force to stop motion
How does static friction actually prevent motion?
Add all the x and y components of each angle, then use the Pythagorean theorem to find the answer To find angle, find the tangent of the sum of the x and y, then add 180 to it
How to mathematically find equilibrant
It increases up to a max. before it is overcome and motion begins
If there is a force trying to cause motion, what happens to static force?
Zero
If there is no force acting on an object, what is the static force?
The equilibrant
Is a force of the same magnitude but opposite direction as the sum of all the other forces acting on an objet
Always positive
Is the coefficient of friction (kinetic or static) positive or negative?
Yes, once the force is greater than the maximum static friction, the object moves and kinetic friction begins to act on it
Is there a limit for static friction?
Static friction
The force exerted on one surface by a second when there is no motion between the two surfaces
Kinetic friction
The fore exerted on one surface by a second surface when the two surfaces rub against each other because one or both of the surfaces are moving
Coefficient of kinetic friction
The lope of a line on a kinetic friction force v. normal force graph; relates frictional force to normal force and depends on the two surfaces in contact
Vector resolution
The process of breaking a vector into its components is sometimes called a
Length and direction
The representation of a vector has both
Components
To determine the _____ of a vector, a coordinate system must be chosen
Once force of static friction is overcome, the force of kinetic friction is what slows down a moving object
What actually stops the moving object?
Kinetic friction
What is always less than the maximum value of static friction
The coefficient of static friction
What's greater, the coefficient of static friction or the coefficient of kinetic friction?
It has magnitude and direction
Why is force a vector?