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.
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)
Define kinetic friction.
The force that opposes the motion of two surfaces sliding against each other.
Define static friction.
The force that opposes the start of motion between two surfaces in contact.
Define the coefficient of kinetic friction ().
A dimensionless quantity representing the 'roughness' between two surfaces in kinetic friction. It relates the kinetic friction force to the normal force.
Define the coefficient of static friction ().
A dimensionless quantity representing the 'stickiness' between two surfaces in static friction. It relates the maximum static friction force to the normal force.
Define normal force ().
The force exerted by a surface that is supporting the weight of an object. It acts perpendicular to the surface.