Hon. Physics Chapter 6: Newton's 2nd Law of Motion
Terms in this set (39)
What is speed (velocity)?
The rate at which distance is covered,
What is acceleration?
The rate at which the velocity is changing.
What can be a change in velocity?
Increasing speed, decreasing speed, or changing direction.
What does negative acceleration mean?
The object is slowing down (decelerating).
What does the net force cause an object to do?
What must happen to an object in order for it to accelerate?
A net force must act on it.
What is the relationship between net force and acceleration?
What is the relationship between acceleration and mass?
Who was the first to realize that both the
of the object will determine its acceleration?
How did Newton express the relationship between acceleration, net force, and mass?
Acceleration = Net Force / Mass
`What is Newton's second law of motion?
Force is equal to mass times acceleration (F=ma).
What is friction?
The force that resists the motion of an object.
What direction does friction always act?
In the opposite direction of motion.
What does frictional force depend on?
1) Kinds of materials (surface roughness)
2) How much the surfaces bare pressed together (weight)
What is static friction?
Friction between two stationary surfaces (no movement even when a force is applied).
What is kinetic friction?
Friction while something is moving.
What is fluid friction?
Friction that occurs as an object pushes aside the fluid it is moving through.
What is friction necessary for?
What can friction convert?
Mechanical energy to heat & sound energy.
Can friction be completely eliminated?
How can friction be reduced?
What is the coefficient of friction?
Number that describes the amount of friction between two surfaces.
What are the three forces acting on something on an inclined plane?
Weight of the object, the frictional force, and the normal force.
How is the vector of the frictional force on an object on an inclined plane related to the surface of the inclined plane?
How does the normal force
Perpendicular to the surface.
With an object on an inclined plane, what is FNormal equal to?
With an object on an inclined plane, what is FFrictional equal to?
What happens as the angle increases on an inclined plane?
The frictional force decreases.
What is pressure?
The weight (force) of an object as it presses on the surface it is laying against.
What is pressure expressed as?
P = F / A
What are the main units for pressure?
Pascals (Pa) = Newtons per square meter
What are commonly used units for pressure?
PSI (pounds per square inch)
What is the relationship between pressure and area?
What is the relationship between pressure and force?
More massive objects have a greater ______.
How do objects accelerate in the absence of air resistance?
At the same time.
What happens as an object falls through air?
They experience air resistance (drag).
What does the amount of drag depend on?
The object's speed and surface area.
What happens when the falling object encounters the same air resistant force as the weight pulling it down?
It is in dynamic equilibrium. (Known as *terminal velocity*)