All Flashcards
What is the effect of increasing the normal force on kinetic friction?
Increasing the normal force increases the magnitude of the kinetic friction force ().
What is the effect of the applied force exceeding the maximum static friction?
The object begins to move, and kinetic friction replaces static friction.
What happens if the coefficient of static friction increases?
It becomes harder to start moving the object because the maximum static friction force increases.
What is the effect of a non-zero net force when kinetic friction is present?
The object will accelerate according to Newton's Second Law ().
What happens when the applied force is less than the maximum static friction force?
The object remains at rest, and the static friction force equals the applied force.
What are the key differences between kinetic and static friction?
Kinetic Friction: Acts on moving surfaces, constant magnitude. | Static Friction: Acts on surfaces at rest, self-adjusting up to a maximum value.
Compare the coefficients of static and kinetic friction.
Coefficient of Static Friction (): Usually greater than , represents the force needed to start motion. | Coefficient of Kinetic Friction (): Usually smaller than , represents the force needed to maintain motion.
Compare the forces involved when an object is at rest versus sliding down an inclined plane.
At Rest: Static friction balances the component of gravity pulling the object down the plane. | Sliding: Kinetic friction opposes the motion down the plane, but the net force results in acceleration.
What is the difference between the formulas for kinetic friction and maximum static friction?
Kinetic Friction: (always equal to this value when sliding) | Maximum Static Friction: (static friction can be any value from zero up to )
Compare the effect of contact area on kinetic and static friction.
Kinetic Friction: Magnitude of kinetic friction force remains constant regardless of the contact area between the surfaces. | Static Friction: The area of contact does not affect the maximum static friction force.
In a diagram of kinetic friction, label the forces acting on a block sliding to the right.
1: Applied Force (right), 2: Kinetic Friction (left), 3: Normal Force (up), 4: Weight (down)
In a diagram of static friction, label the forces acting on a stationary block with an applied force to the right.
1: Applied Force (right), 2: Static Friction (left), 3: Normal Force (up), 4: Weight (down)
Label the forces acting on a block sliding down an inclined plane with kinetic friction.
1: Weight (down), 2: Normal Force (perpendicular to plane), 3: Kinetic Friction (up the plane), 4: Component of Weight parallel to the plane (down the plane)
Label the forces acting on a block at rest on an inclined plane due to static friction.
1: Weight (down), 2: Normal Force (perpendicular to plane), 3: Static Friction (up the plane), 4: Component of Weight parallel to the plane (down the plane)
Label the forces on a free body diagram of an object being pushed horizontally with friction.
1: Applied Force (horizontal), 2: Friction Force (opposite applied force), 3: Normal Force (vertical), 4: Gravitational Force (vertical)