All Flashcards
Compare and contrast static and kinetic friction.
Static Friction: Acts on stationary objects, prevents motion, adjustable up to a maximum value. | Kinetic Friction: Acts on moving objects, opposes motion, constant value.
What are the key differences between and ?
: Coefficient of static friction, applies to objects at rest, usually greater than . | : Coefficient of kinetic friction, applies to objects in motion, usually less than .
Compare the force of static friction to the applied force before movement occurs.
Static Friction: Equal in magnitude and opposite in direction to the applied force, up to the maximum static friction force. | Applied Force: The external force attempting to initiate movement.
Compare the force of kinetic friction to the applied force when an object is moving at a constant velocity.
Kinetic Friction: Equal in magnitude and opposite in direction to the net applied force. | Applied Force: The external force that, in combination with kinetic friction, results in zero net force and constant velocity.
Compare the effect of surface area on static vs kinetic friction.
Static Friction: Magnitude is independent of the contact area between the surfaces. | Kinetic Friction: Magnitude is independent of the contact area between the surfaces.
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)
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.