Acceleration
Objects that are changing their speed or their direction are said to be accelerating. The
rate at which the speed or direction changes is referred to as acceleration.
Aerodynamics
Having a shape that reduces air resistance.
Balanced Force
A balanced force results whenever two or more forces act upon an object in such a way
as to exactly counteract each other.
Centripetal Force
Motion along a curve or through a circle is always caused by a centripetal force. This is a
force that pushes an object in an inward direction.
Energy
The ability to do work.
Force
A force is a push or a pull acting upon an object.
Friction
Friction is a force that resists the motion of an object. Friction results from the close
interaction between two surfaces that are sliding across each other.
Gravity
Any two objects with mass attract each other with a type of force known as a
gravitational force. The strength of this force depends upon the mass of the two objects
and the distance between them.
Inertia
Inertia is a tendency of an object to resist change in its state of motion.
Kinetic Energy
Kinetic energy is the energy possessed by an object because of its motion. All moving
objects have kinetic energy. The amount of kinetic energy depends upon the mass and
speed of the object.
Mass
The mass of an object is a measurement of the amount of material in a substance. Mass
refers to how much "stuff" is there. Elephants are very massive, since they contain a lot
of "stuff."
Momentum
Momentum pertains to the quantity of motion that an object possesses. Any mass that is
in motion has momentum. In fact, momentum depends upon mass and velocity, or in
other words, the amount of "stuff" that is moving and how fast the "stuff" is moving.
Motion
The action or process of moving.
Period
A motion that repeats itself in cyclic fashion is said to be periodic. The time for one
complete cycle is known as the period of the motion.
Potential Energy
Potential energy is the energy possessed by an object because of its height above the
ground. The amount of potential energy possessed by an object depends on its mass
and its height.
Speed
Speed is a measurement of how fast an object is moving. Fast
-
moving
objects can cover
large distances in a small amount of time. They are said to have a high speed.
Unbalanced Force
A force that causes an object to change its motion.
Velocity
The velocity of an object refers to the speed and direction in which it moves.
Weight
Weight is a measurement of the gravitational force acting on an object.
Work
When a force is used to move an object through a distance.
NEWTON’S LAWS OF MOTION
Newton's First Law of Motion
An object at rest or in uniform motion in a straight line will remain at rest or in the same
uniform motion unless acted upon by an unbalanced force. This is also known as the law
of inertia.
Newton's Second Law of Motion
The acceleration of an object is directly proportional to the total unbalanced force
exerted on the object, and is inversely proportional to the mass of the object (in other
words, as mass increases, the acceleration has to decrease). The acceleration of an
object moves in the same direction as the total force. This is also known as the law of
acceleration.
Newton's Third Law of Motion
If one object exerts a force on a second object, the second object exerts a force equal in
magnitude and opposite in direction on the object body. This is also known as the law of
interaction.
