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.
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)