Mass:

A measurement of resistance for an object to being moved by a force. This resistance is called inertia. *Think of mass as a measurement of stubbornness* Mass is measured in kilograms (kg).


Velocity:

A measurement of the speed AND direction of an object. Velocity has units of length/time. ( For example: A car traveling at 55mph is a speed. A car traveling North at 55mph is a velocity.)


Acceleration:

A change in velocity of an object. This change can be either a change in the speed or a change in the direction or both. Acceleration has units of length/time^2


Inertia:

The resistance of an object to being accelerated by a force. (See Mass)


Momentum:

Tendency for an object to keep moving with the speed and direction that it is going. Momentum = mass x velocity


Pressure:

The force per unit area that is exerted on some object. For instance, the pressure inside a balloon is determined by the number of atoms hitting the wall of the balloon every second. Units lbs/in^2, N/m^2, Pascals.


Temperature:

A measure of random motion of molecules or atoms within a substance or as a gas.


Force:

The instigator or influence of motion that causes an object to be accelerated. Force = mass x acceleration. Units: Newtons(N) where 1N = 1kg-m/s^2


Kinetic Energy:

Energy of motion = 1/2mv^2 has units of Joules(J) where 1 Joule = 1kg m^2/s^2


Potential Energy:

Energy that an object has by virtue of its position in a force field. For an object suspended above the surface of the earth, PE = mgh. Units: Joules(J).


G:

Gravitational acceleration at the earth's surface = 9.8 m/s^2 This acceleration is due to the gravitational interaction with the earth and an object located on or near the earth's surface.


Impulse:

A force being applied onto an object for a specific amount of time which results in the object having a change in momentum. Impulse = force x time = change in momentum. (Ft = change in mv)


Weight:

The gravitational force on an object located at or near the earth's surface. Weight = mass x G


Joule:

A unit of mechanical energy. 1Joule = 1kg m^2/s^2


Calorie:

A unit of heat energy. 1 cal = 4.186 Joules(J)