PS+5+-+4th+Period+Brown

[] (need more help, click here) __**Balanced force**__- forces on a object that combine to give a zero net force and do not change the motion of the object. __**Gravity**__- attractive force between two objects that depends on the masses of the objects and the distance between them.
 * __Force__**- a push or pull exerted on an object.
 * __Net force__**- the sum of the forces that are acting on an object.
 * __Inertia__**- resistance of an object to a object to a change in its motion.
 * __Mass__**- the amount of matter in an object.
 * __Acceleration__**- the rate of change of velocity.
 * __Newtons second law__**- states that the acceleration of an object is in the direction as the net force on the object, and that the acceleration equals the net force divided by the mass. EX: F=ma.
 * __Friction__**- force that opposes the sliding motion between two touching surfaces.
 * __Static friction__**- frictional force that prevents two surfaces from sliding past each other.
 * __Sliding friction__**- frictional force that opposes the motion of two surfaces sliding past each other.
 * __Air resistance__**- force that opposes the motion of objects that nove through the air.
 * __Law of universal gravitaion__**- law that there is a force of attraction between all objects in the universe.
 * __Distance__**- how far an object moves.
 * __Weight__**- gravitational force exerted on an object.


 * __The Concepts of Motion__:**


 * __Motion__**-cover the distance in the shortest amount of time.
 * __Reference point__**- is needed to determine the position of an object
 * __Distance__**- how far an object moves.
 * __Displacement__**- distance and direction of an object's change in position from the starting point.
 * __Speed__**- distance an object travels per unit of time.
 * __Instantaneous speed__**- speed of an object at a given point in time; is constant for an object moving with constant speed, and changes with time for an object that is slowing down or speeding up.
 * __Average speed__**- total distance an object travels divided by the total time it takes to travel that distance.
 * __Velocity__**- the speed and direction of a moving object.**__Key Concepts:__**
 * __Acceleration__**- rate of change of velocity; can be calculated by dividing the change in the velocity by the time it takes the change to occur.**__Graphing Linear

Motion:__**

__**Unbalanced force**__- is needed to make a resting object move, to bring a moving object to rest, or to change the direction of a moving object.
 * __Distance vs.Time__**- distance is how far it has moved and time is the amount of seconds, hours,minutes.
 * __Displacement vs.Time__**- is the distance and direction of an objects change in position.
 * __Constant speed__**- is movement at a fixed distance per unit of time
 * __Newtons First Law(Law of Inertia)-__** Every object in a state of uniform motion tends to remain in that state of motion unless an external force is applied to it.
 * __Rolling friction__**- is caused primarily by the interference of small indentations formed as one surface rolls over another.
 * __Terminal Velocity__**-the velocity at which a falling body moves through a medium, as air, when the force of resistance of the medium is equal in magnitude and opposite in direction to the force of gravity.
 * __Gravitational Force__**-the force of attraction between all masses in the universe; especially the attraction of the earth's mass for bodies near its surface
 * __Projectile Motion__**- Is any object that has been thrown, shot, or launched


 * __Newton's Third Law__:** [] (need more help, click here)


 * __Projectile Motion__-** Projectile motion refers to the motion of an object projected into the air at an angle.
 * __Centripetal Force__-** The force, acting upon a body moving along a curved path, that is directed toward the center of curvature of the path and constrains the body to the path.
 * __Newton's Third Law__-** Action and reaction are equal and opposite.
 * __Momentum__-** Force or speed of movement, as of a physical object or course of events.


 * __Universal Force__:** [] (need more help, click here)


 * __Newton's Law of Universal Gravitation__-** Gravitational attraction between bodies with mass.
 * __Mass__-** Is the amount of matter an object has.
 * __Attractive Force__-** The force by which one object attracts another.
 * __Distance__-** The force by which one object attracts another.

//** Newtons Laws ** []


 * __Great examples of Newtons Law's :D

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Virtual Lab of Newton's Second Law of Motion

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=Relative Motion, Speed, Velocity and Acceleration= //[]// Skaters showing newtons third law. Unless an object is acted upon by an outside force, the object will stay at rest if already at rest or will continue moving in a straight line at constant speed**. Watch** **the driver!**

Shows how friction acts on a rolling ball