PS+5+-+3rd+Period+Brown

=Motion = **__The Basics of Motion__**  Acceleration- rate of change of velocity can be calculated by dividing the change in velocity by the time it takes for the change to occur Split times- timing at intervals
 * Motion: occurs when an object changes position
 * Reference point- allows you to determine whether an object has moved
 * relative motion- when you are moving relatively to things around you
 * Distance- describes how far an object has moved
 * Displacement- the distance and direction that has changed from a starting point
 * Speed- the time it takes to travel a distance
 * [[image:instant2.gif width="317" height="174"]]
 * Instantaneous speed- speed being traveled at that moment
 * Average speed- measured as distance over time
 * Velocity- both speed and direction of motion
 * <span style="font-family: Arial, Helvetica, sans-serif;">Direction- the area an object is moving
 * <span style="font-family: Arial, Helvetica, sans-serif;">Velocity (v)=distance (d) / time (t)
 * <span style="font-family: Arial, Helvetica, sans-serif;">Time- rate it takes you to do something


 * __Graphing Linear Motion__**
 * <span style="font-family: Arial, Helvetica, sans-serif;">distance vs. time- tells you how far something has traveled in a certain time
 * <span style="font-family: Arial, Helvetica, sans-serif;">displacement vs. time- tells you about traveling in different directions
 * <span style="font-family: Arial, Helvetica, sans-serif;">story graph- graph that tells a story, shows different paths traveled
 * <span style="font-family: Arial, Helvetica, sans-serif;">at rest- the graph is flat, after each time the object is still at the same distance, which means it has not moved
 * <span style="font-family: Arial, Helvetica, sans-serif;">constant speed- diagonal straight line, distance increases the same amount from point to point
 * <span style="font-family: Arial, Helvetica, sans-serif;">accelerating- curved graph, can be slowing down or speeding up
 * <span style="font-family: Arial, Helvetica, sans-serif;">towards the start - on a displacement graph, a slope is moving towards the start
 * <span style="font-family: Arial, Helvetica, sans-serif;">away from the start- on a displacement graph, a positive slope is moving away from the start

<span style="font-family: Arial, Helvetica, sans-serif;">

=<span style="font-family: Arial, Helvetica, sans-serif;">Forces =

<span style="font-family: Arial, Helvetica, sans-serif;"><span style="color: rgb(242,186,181); font-family: 'Comic Sans MS',cursive;">**__Intro to Forces__** <span style="font-family: Arial, Helvetica, sans-serif;"><span style="color: rgb(242,186,181); font-family: 'Comic Sans MS',cursive;">**__Newton's Second Law__** <span style="color: rgb(242,186,181); font-family: 'Comic Sans MS',cursive;"> <span style="font-family: Arial, Helvetica, sans-serif;"><span style="color: rgb(242,186,181); font-family: 'Comic Sans MS',cursive;">**__Newton's Third Law__** <span style="font-family: Arial, Helvetica, sans-serif;"><span style="color: rgb(242,186,181); font-family: 'Comic Sans MS',cursive;">**__Universal Gravitation__**
 * <span style="font-family: Arial, Helvetica, sans-serif;">Force- a push or pull that one body exerts on another
 * <span style="font-family: Arial, Helvetica, sans-serif;">Balanced force- equal forces exerted on an object
 * <span style="font-family: Arial, Helvetica, sans-serif;">[[image:together.gif]]
 * <span style="font-family: Arial, Helvetica, sans-serif;">Unbalanced force- unequal forces exerted on an object
 * <span style="font-family: Arial, Helvetica, sans-serif;">[[image:blue1.gif]]
 * <span style="font-family: Arial, Helvetica, sans-serif;">Net force- when two or more forces act on an object at the same time
 * <span style="font-family: Arial, Helvetica, sans-serif;">[[image:netf1.gif width="200" height="150"]]
 * <span style="font-family: Arial, Helvetica, sans-serif;">Inertia- the tendency of an object to resist any change in its motion
 * <span style="font-family: Arial, Helvetica, sans-serif;">Mass- the amount of matter in an object
 * <span style="font-family: Arial, Helvetica, sans-serif;">Law of Inertia (Newton's First Law)- An object at rest will stay at rest and an object in motion will continue moving at a constant velocity unless acted upon by a net force
 * <span style="font-family: Arial, Helvetica, sans-serif;">Newton's Second Law
 * <span style="font-family: Arial, Helvetica, sans-serif;">force (f)= mass (m) x acceleration (a)
 * <span style="font-family: Arial, Helvetica, sans-serif;">Friction- the force that opposes motion between two surfaces that are touching each other
 * <span style="font-family: Arial, Helvetica, sans-serif;">Sliding- the force that opposes motion of two surfaces sliding past each other
 * <span style="font-family: Arial, Helvetica, sans-serif;">Rolling- the friction between a rolling object and the surface it rolls on
 * <span style="font-family: Arial, Helvetica, sans-serif;">Static- the friction between two surfaces that are not moving past each other
 * <span style="font-family: Arial, Helvetica, sans-serif;">Air Resistance- the resistant force to gravity
 * <span style="font-family: Arial, Helvetica, sans-serif;">Terminal Velocity- the highest velocity a falling object will reach
 * __<span style="font-family: Arial, Helvetica, sans-serif;">Gravity __**
 * <span style="font-family: Arial, Helvetica, sans-serif;">Law Of Gravitation- there is a force of attraction between all objects in the universe
 * <span style="font-family: Arial, Helvetica, sans-serif;">Gravitational force- attracted by anything that has mass
 * <span style="font-family: Arial, Helvetica, sans-serif;">Gravity- a long range force that attracts anything that has mass
 * <span style="font-family: Arial, Helvetica, sans-serif;">Weight- gravitational force exerted on an object
 * <span style="font-family: Arial, Helvetica, sans-serif;">Projectile Motion- the curved path of a projectile
 * <span style="font-family: Arial, Helvetica, sans-serif;">[[image:gun.gif]]
 * <span style="font-family: Arial, Helvetica, sans-serif;">Centripetal force- acceleration towards the center of the curved or circular path
 * <span style="font-family: Arial, Helvetica, sans-serif;">Newton's Third Law- For every action force, there is an equal and opposite reaction force.
 * <span style="font-family: Arial, Helvetica, sans-serif;">Momentum = mass x velocity
 * <span style="font-family: Arial, Helvetica, sans-serif;">attractive force- the forces that attract an object to another
 * <span style="font-family: Arial, Helvetica, sans-serif;">force acceleration- the speed in which a force is going

<span style="font-family: Arial, Helvetica, sans-serif;">Questions:

1. Which of the following best describes the difference between speed and velocity? A. Speed includes distance and direction while velocity includes only distance B. Speed includes distance and direction while velocity includes only direction C. Velocity includes distance and direction while speed includes only direction
 * D . Velocity includes distance and direction while speed includes only distance**

2. Sound travels at a speed 330 meters/seconds if John hears police siren 165 meters away, how long did it take for the sound to travel from the siren to John? A. 0.5 seconds C. 5 seconds D. 20 seconds
 * B . 2 seconds**

3. A boat leaves the dock and travels west reaching a velocity of 6 meters/second after 3 seconds what is its acceleration? A. 0.5 m/s sq. C. 6 m/s sq. D.18 m/s sq.
 * B. 2 m/s sq.**

4. Suppose you roll a basketball and a baseball toward each other. How does this affect the force of gravity they exert on one another? B. it decreases C. it stays the same D. it disappears
 * A. it increases**

5. The mass of two objects is an important factor in determining the force of gravity between them? What is the second factor? A. Their volume. C. Their diameter. D. Their density.
 * B. The distance between them.**

6. Which of the following is a force that can oppose or change motion? A. gravity. B. air resistance. D. all of the above.
 * C. friction.**

7. A passenger in a car that suddenly stops will: B. lean backward. C. lean to the right. D. feels no motion.
 * A. lean forward.**

8. The Moon has 1/6 the gravity of Earth, which is approximately 9.8 m/s^2. If something has a mass of 12 kg, approximately what will it weigh on the Moon? B. 12 kg C. 20 N D. 2 N
 * A. 2 kg**

9. Mariah and Charley each pull at opposite ends of a rope. Charley is stronger. Who will move backwards? A. The rope will move but Mariah and Charley won't. B. Both Mariah and Charley will move backwards. C. Mariah will move backwards.
 * D. Charley will move backwards.**

10. A car engine works harder to accelerate from zero to 10 km/hr than it does to maintain a 10 km/hr velocity. Why is this? A. Because static friction is harder to overcome than kinetic or rolling friction. B. Because static friction is easier to overcome than kinetic or rolling friction. D. Because static friction is easier to overcome than potential friction.
 * C. Because static friction is harder to overcome than potential friction**.

11. In order to move a wheelbarrow a constant force is exerted? Which of the following will increase its acceleration? A. increasing the mass of the wheelbarrow C. reversing the direction of the wheelbarrow D. changing the color of the wheelbarrow
 * //__ B. __// decreasing the mass of the wheelbarrow**

12.Which of the following best describes the relationship between inertia and mass? A. a greater mass means that something is easier to slow down or speed up. B. the amount of inertia something has is equal to its mass D. the greater the mass of an object, the less inertia it has
 * C. the greater the mass of an object, the greater the inertia it has**

13.A ball has a mass of 1.5 kg. What is the net force on the ball if its acceleration is 55 m/s squared? A. 36.7 N C. 56.5 N D. 53.5 N
 * B. 82.5 N**

14. Your weight on Mars is only about 1/3 your weight on Earth. Which reason best explains this? A. It is closer to the sun. C. It has a greater force of gravity than Earth. D. It is farther from the sun.
 * B. It has a smaller force of gravity than Earth**.

15. During recess at school, Tara and her friends enjoy bouncing tennis balls against a brick wall. According to Newton's Third Law of Motion, what actually occurs? B. The force that t he ball exerts on the wall will be greater than the force that the wall exerts on the ball. C. Both forces will be equal. D. The wall will accelerate the ball's velocity in the same direction it was traveling initially.
 * A. The force that the wall exerts on the ball will be greater than the force that the ball exerts on the wall.**

Helpful Websites

http://library.thinkquest.org/C0110840/instant.htm <span style="font-family: Arial, Helvetica, sans-serif;"><span style="color: #000000; font-family: 'Comic Sans MS', cursive;">http://www.usoe.k12.ut.us/CURR/SCIENCE/sciber00/8th/forces/sciber/forces.htm http://hyperphysics.phy-astr.gsu.edu/Hbase/grav.html http://id.mind.net/~zona/mstm/physics/mechanics/forces/netForce/netForce.htm http://hyperphysics.phy-astr.gsu.edu/hbase/mass.html