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Near the surface of earth, acceleration due to gravity is 9.8 m/s^2
NEWTON'S LAWS OF MOTION:
Of Inertia) (clothes on the ground, throwing a ball)
2) Acceleration the object. AcccelrationAccelration = net pg. 351) (tennis vs bowling ball; wagon -
3) If opposite reaction. (jump - push the ground with your feet)
Key Concept:
1 - The Nature of Forces

Fluid Friction- occurs when a solid object moves through a fluid. (Machine parts move through oil - fluids.)
Mass- a measurement of the same amount of matter in an object.
a planet. (Are you heavier on earth or on the moon? Why?)
Free Fall- when the only force acting against an object is gravity.
the air. (falling acorn vs. falling leaf)
Terminal Velocity- the greatest velocity a falling object reaches.
Projectile- an object that is thrown.
in motion. (Moving forward when brakes are applied suddenly)
Acceleration= net force/mass
Momentum- is a characteristic of a moving object that is related to the mass and the velocity of a moving object.
Momentum= mass x velocity
The unit for momentum is kg X m/sec.
Conservation: Refers to the condition before and after an event.
Satellite- any object that orbits another object in space.
Centripetal Force- any force that causes an object to move in a circular path.
Law of Universal Gravitation: States that the force of gravity acts between all objects in the universe.
REVIEW Page 344,45 for definitions
Near the surface of earth, acceleration due to gravity is 9.8 m/s^2
NEWTON'S LAWS OF MOTION:
1) An object at rest will remain at rest and an object moving at a constant velocity will continue moving at a constant velocity unless it is acted upon by an unbalanced force. (The Law Of Inertia)
2) Acceleration depends on the mass and the on the net force acting on the object. Acccelration = net force / mass. (Insert formula pg. 351)
3) If one object exerts a force on another object, than the second object exerts a force of equal strength in the opposite direction of the first object. For every action, there is an equal but opposite reaction.
Key Concept:
1 - The Nature of Forces
In free fall, the force of gravity is an unbalanced force, which causes an object to accelerate.
3 -
ANAn object at
Acceleration depends on the objects mass and on the net force acting on the object.
4 -
The total momentum of any group of objects remains the same, or is conserved, unless outside forces act on the objects.
5 -
a downward actionj foceaction force exert an
Satellites in orbit around Earth continuously fall toward Earth, but because Earth is curved they travel around it.

Newton- the strength of a force is measure in this SI unit.
Net Force- the combination of all forces acting on an object.
change direction. Can cause
Balanced Forces- equal forces acting on one object in opposite direction.
Friction- the force that two surfaces exert on each other when they rub against each other.
not moving. (sliding a desk across the floor - neither object is moving.)
Sliding Friction- each other. (Brakes stopping a bike)
Rolling Fiction- When an object rolls across a surface.
a fluid. (Machine parts move through oil - fluids.)
Mass- a measurement of the same amount of matter in an object.
Weight- the force of gravity on a person or object at the surface of a planet.
Satellite- any object that orbits another object in space.
Centripetal Force- any force that causes an object to move in a circular path.
Law of Universal Gravitation: States that the force of gravity acts between all objects in the universe.
Key Concept:
1 - The Nature of Forces

Unbalanced forces acting on an object result in a net force and cause a change in the object's motion.
Balanced forces acting on an object do not change in the object's motion.
2)2 -
The strength of the force of friction depends on two factors: how hard the surfaces push together and the types of surfaces involved.
Two factors affect the gravitational attraction between objects: mass and distance.
In free fall, the force of gravity is an unbalanced force, which causes an object to accelerate.
3)3 -
AN object at rest will remain at rest, and an object moving at a constant velocity will continue moving at a constant velocity, unless it is acted upon by an unbalanced force.
Acceleration depends on the objects mass and on the net force acting on the object.
4)4 -
If one object exerts a force on another object, then the second object exerts force of equal strength in the opposite direction on the first object.
The momentum of a moving object is equal to its mass times its velocity.
The total momentum of any group of objects remains the same, or is conserved, unless outside forces act on the objects.
5)5 -
A rocket can rise into the air because the gases it expels with a downward actionj foce exert an equal but opposite reaction force on the rocket.
Satellites in orbit around Earth continuously fall toward Earth, but because Earth is curved they travel around it.

Newton- the strength of a force is measure in this SI unit.
Net Force- the combination of all forces acting on an object.
direction. Can cUSEcause
Balanced Forces- equal forces acting on one object in opposite direction.
Friction- the force that two surfaces exert on each other when they rub against each other.

Newton- the strength of a force is measure in this SI unit.
Net Force- the combination of all forces acting on an object.
change direction. Can cUSE
Balanced Forces- equal forces acting on one object in opposite direction.
Friction- the force that two surfaces exert on each other when they rub against each other.
Satellite- any object that orbits another object in space.
Centripetal Force- any force that causes an object to move in a circular path.
Key Concept: 1)
1 - The Nature of Forces
Like velocity and acceleration, a force is described by its strength and by the direction which it acts.
Unbalanced forces acting on an object result in a net force and cause a change in the object's motion.
Balanced forces acting on an object do not change in the object's motion.
2)
The strength of the force of friction depends on two factors: how hard the surfaces push together and the types of surfaces involved.
Two factors affect the gravitational attraction between objects: mass and distance.

Motion- an object is moving if its distance from another object is changing.
a object uysedused for comparison to dterminedetermine if something is in motion.motion (tree, sign or building)
International System communicate clearly. (1000 m - 1 KM)
Average Speed- the total distance traveled over the total time.
Instantaneous speed- the rate at which an object is moving at a given instant in time.
in a givegiven direction. (air traffic controllers)
Slope- the steepness of a line on a graph.
Acceleration- the rate at which velocity changes.
Key Concepts:
1) A
n1 - Describing and Measuring Motion
an object is
Scientists use SI units to describe the distance an object moves.
2)2 - Speed and Velocity
If you know the distance an object travels in a certain amount of time, you can calculate the speed of an object.
Speed= distance/time
When you know both the speed and direction of an object's motion, you know the velocity of the object.
You can show the motion of an object on a line graph in which you plot distance versus time.
Slope= rise/run
3) (rate of change) slope=speed
3 - Acceleration
In science acceleration refers to increasing speed, decreasing speed, or changing direction.
To determine the acceleration of an object moving in a straight line, you must calculate the change in speed per unit of time.

To describe a reaction accurately, a chemical equation must show the same number of each type of atom on both sides of the equation.
Many chemical reactions can be classified in one of three categories: synthesis, decomposition, or replacement.
3 - Controlling Cheming Reactions
All chemical reactions need a certain amount of activation energy to get started.
Chemists can control rates of reactions by changing factors such as surface area, temperature, and concentration, and by using substances called catalysts and inhibitors.

All chemical reactions need a certain amount of activation energy to get started.
Chemists can control rates of reactions by changing factors such as surface area, temperature, and concentration, and by using substances called catalysts and inhibitors.
4 - Fire and Fire Safey
The following three things are necessary to start and maintain a fire: fuel, oxygen, and heat.
If you know how to prevent fires in you home and what to do if a fire starts, you are better prepared to take action.