Unit1_JinR

=**Day 1**=

toc

** Lesson 2 - ** **Kinetics**
__** In Class **__


 * ** Vocab **
 * Distance-How far something travels. Total area covered by an object from origin to end point.
 * Displacement-Net change in potion, relative to the starting point.Takes direction into account.
 * Speed-Rate of change of position, how fast something moves, distance/time.
 * Velocity-Rate of change of potion, based on displacement.
 * Acceleration-How fast speed or velocity changes.
 * Time-n/a
 * Scalar- Describes distance traveled.
 * Vector- Distance traveled and direction
 * ** Units **
 * Distance-Meters
 * Displacement- Meters
 * Speed- Meters/Second
 * Velocity- Meters/Second
 * Acceleration- Meters/Second^2
 * Time- Seconds
 * ** Symbol **
 * Distance- d
 * Displacement- d
 * Speed- v
 * Velocity- v
 * Acceleration- a
 * Time- t
 * ** Type of Quantity **
 * Distance- Scalar
 * Displacement- Vector
 * Speed- Scalar
 * Velocity- Vector
 * Acceleration- Vector
 * Time- n/a
 * ** Types of Motion (4 only) **
 * At rest- no motion.
 * Constant velocity- no change in your velocity, covering same distance in the same time. V=d/t
 * Increasing velocity- starting slower and steadily getting faster.
 * Decreasing velocity- starting faster and steadily getting slower.
 * ** Lab-Constant Speed **
 * Objective: What does a graph of Constant Speed look like?
 * Hypothesis: A linear line with a positive slope.
 * Rational: A linear line due to a starting point of zero speed and it continues on till it stops and the amount of time and distance covered is constant. A postive slope because both time and distance are increasing.
 * Data & Observation : [[file:Lab1.xlsx]]
 * [[image:B5.PNG width="497" height="294"]]
 * [[image:b4.PNG width="261" height="359"]]
 * Conclusion: The graph of constant speed is a linear line with the slope representing the speed the ball was traveling and the R^2 value representing how well the line of best fit fits the data and due to the fact that the R^2 value being above .95, the line is appropriate for the graph. The show that the speed of the steep ball, .8622, is faster than the shallow ball, .6936 m/s.

__** At Home﻿ **__


 * ** Describing Motion with Words **
 * Kinetics, a part of physics, is the study of motion. Do not memorize information. Kinematics, a branch of kinetics, is describing motion with words, diagrams, numbers, graphs, and equations.
 * Though physics is a math oriented science, words can still describe it. To describe kinetics with more accurate terms are distance, displacement, speed, velocity, and acceleration. To describe the quantitative part of motion, use the words scalar to represent magnitude of change alone, but to include direction, use vectors.
 * Though distance and displacement seem similar, they are not. Distance is a scalar quantity, while displacement is a vector quantity, so you can have a distance of 10 meters by going north 5 meters and south 5 meters, your displacement will be zero.
 * The difference between speed and velocity is similar to the difference between distance and displacement. Speed is a scalar quantity, while velocity is a vector quantity.
 * Speed is described as a rate of distance over time. High speed is a large amount of distance covered over a small amount of time, while low speed is a small amount of area covered in a large amount of time. No speed is an object that does not move.
 * Velocity is the change in potion over time, so while a great amount of distance could be covered in a little time, if the starting point and endpoint are the same, then there is no velocity. Velocity is a vector quantity, since it takes direction into account and must have the direction when describing it. So if an object moving northwards it could be described as having a northwards velocity.
 * Science most objects in motion do not stay at the same speed all the time, its speed can be described in two ways. Instantaneous speed is a speed at a given moment while average speed is the total distance over the total time. A person could be traveling at 3 m/s for instantaneous speed, but have an average speed of 1.5 m/s. Average speed can be calculated by total change in potion over time.
 * Constant speed is an object traveling across an area with no change to the rate of distance over time. Changing speed is an object that slow, speeds up or stops over a certain amount of time.
 * Acceleration is a vector quantity where a velocity changes, it does not describe something that moves fast, if there is no change to speed or position. The speed of an object can change at the same amount each second, so it can be said that it has a constant acceleration. If it does not change by the same amount it is not constant acceleration, but it is still accelerating.
 * When an object is accelerating, like free-falling objects, the velocity is constantly changing and must be taken from per second. With constant acceleration, there is a direct correlation between the distance traveled and the time squared. To calculate velocity, divide the change in velocity, or the final velocity minus the initial velocity, by time. It can be topically described as m/s/s, mi/hr/s, km/hr/s, or m/s^2.
 * Acceleration describes not only if an object speeds up or slows down, but also the change in distance, positive or negative. When an object slows down it is described as going in the opposite direction or having a negative velocity.
 * ** Describing Motion with Position vs. Time Graphs **
 * A position time graph describes the motion of an object.
 * An object with a constant, rightward (+) velocity will have a graph that shows a line with positive slope.
 * An object with a changing, rightward (+) velocity that is speeding up will have a graph that curves upwards.
 * An object with a constant, leftward (-) velocity will have a graph that shows a line with a negative slope.
 * An object with a changing, leftward (-) velocity that is going from fast to slow will have a graph that curves that is first steep then becomes shallow.
 * An object with a changing, leftward (-) velocity that is going from slow to fast will have a graph that curves that is first shallow then becomes steep.
 * The slope will change depending on the velocity. If one is positive or changing then the other is positive or changing, respectively. If object A is moving faster than object B than object A will have a steeper slope than object B, this applies to both positive moving objects and negative moving objects.
 * In a position time graph, the slope represent the change of position from the origin by an object per time and if the object does not change position than the graph has a 0 slope. The slope of a position time graph equals the velocity of an object.
 * To calculate the slope of a graph is equal to the change in y over the change in x or rise over run.
 * Cute little [|video] based on describing the difference between speed and velocity.

=**Day 2**=

** Lesson 3 -﻿ Motion Diagrams **
__**In Class**__


 * **Motion Diagrams**
 * Represent the qualitative representation
 * Relative size and directions of velocity and acceleration
 * **Symbols**
 * Arrow -->
 * Space ....
 * **Motion diagram of speed**
 * At rest (v=0) (a=0)
 * Constant
 * Slow rightward (+) (--> --> -->) (a=0)
 * Fast rightward (+) (> > >) (a=0)
 * Slow leftward (-) (<-- <-- <--) (a=0)
 * Size of velocity vector
 * Direction of vectors
 * Increasing ( . -> --> --->) (a -> +a)
 * Velocity and acceleration point in the same direction
 * Decreasing (---> --> -> .) (a <- -a)
 * Velocity and acceleration point in opposite direction
 * **Convention**
 * Agreement on what is what
 * Upwards or rightwards is positive
 * Downwards or leftward is negative
 * Use notation to show a difference from convention
 * **Practice**
 * 1) assume to the right is upwards motion (> ---> --> -> .) (a <- -a)
 * 2) assume to the right is downhill motion (--> --> --> --> -->) (a=0)
 * 3) assume to the right is downhill motion) (. -> --> ---> >) (a -> +a)
 * 4) assume to the right is upwards motion (< <--- <-- <- .) (a -> -a)
 * ** Ticket tape diagram **
 * Label the beginning
 * No speed (X)
 * Constant speed (X...X...X...X...X...X)
 * Increasing speed (X.X..X...X....X.....X)
 * Decreasing speed (X.....X....X...X..X.X)

__**At Home**__


 * **Describing Motion with Diagrams**
 * If the physical world can be seen, then physics can be visualized, because physics deals with the physical world. So, visuals are necessary to understand it. Everybody has a different way of learning and one must get use to their own way.
 * Ticket tapes are one way to visualizes speed. A device makes a dot on a tape as the tape is pulled through it. The difference in the spacing of the dots represents the speed the object is moving, larger spaces means faster speed. A constant distance between dots is constant speed, different distance means acceleration.
 * Vector diagrams represent direction and speed of an object. The size of a vector equals the relative speed of the object at the time. Size of a vector is constant, then speed is constant, if the size of the vector is steadily increasing, then it is accelerating. Vector diagrams will become more important. Vectors are all relative to something else.
 * **Describing Motion with Velocity vs. Time Graphs**
 * On a velocity versus time graph, an object with constant speed is a horizontal line, while an object that is accelerating has a linear line with a slope. The slope has a relation to the speed. If a line is sloping towards zero than there is decrease in speed, away than there is an increase, neither is a constant speed. Objects that have a slope bellow the x axis have a negative velocity or in other words have a leftward velocity.
 * The slope of the linear line depends on the the acceleration. The faster something accelerates, the steeper the slope. Multiple slopes can be combined in a single graph to represent the increase, decrease, and the constant speed of an object.
 * In a velocity versus time graph, the area between the axises and the slope is the displacement. If the area covered in an amount of time is a rectangle than A=b*h, triangle is A=1/2(b*h), and trapezoid is A= 1/2(b*(h 1 ﻿+h ﻿2 ﻿).

** Lesson 4 -Acceleration Diagram **
__**In Class**__


 * **Free Fall Lab**
 * Accurate is getting close or correct to the right answer
 * Pension is using the tool correctly meaning off by the same amount
 * Objective: What is acceleration due to gravity?
 * Hypothesis: The rate of a falling object should steadily increase at a rate of 9.8 meters per second.
 * Rational: I saw the rate of acceleration in a textbook.
 * To begin, I hung the spark timer on the ceiling. I threaded the spark tape through the spark timer that was set to 60 Hz. I attached the 200 gram weight to the side that was threaded. I push the weight and spark tape as close to the spark tape as I could, started the spark timer then dropped the weight. I took the tape, found where the wheight hit the floor and removed all the points afterwards. I measured the distance between the dots and add them into the data table.
 * Data Table [[image:Datatable-lab2.PNG]]
 * Graph[[image:Graph-Lab2.PNG]]
 * Analysis/Calculation
 * Rate of acceleration
 * Mine: 4.6465*2=9.293 m/s
 * Class 4.54*2= 9.08 m/s
 * Percent Error
 * (abs(9.8-9.293)/9.8)*100%
 * (abs(9.8-9.293)/9.8)*100%
 * (.507/9.8)*100%
 * .0517*100%
 * 5.17% Error
 * Percent Difference
 * (abs(9.08-9.293)/9.08)*100%
 * (.213/9.08)*100%
 * .0235*100%
 * 2.35% Difference
 * The graph means that as the object falls its velocity is increasing or that the object is accelerating. The shape of the graph is from the constant acceleration of the free falling weight. The curve is from the changing instantaneous speed. The slope is the increasing velocity. The percent error is low enough that the discrepancy is due to a minor factor and the small percent difference shows that most people got a small error. The error could come from the friction from going over the spark timer and through it. The b value could be from a discrepancy of counting from a dot that is not the origin dot.
 * [[file:Lab2.xlsx]]
 * Types of motion
 * MD
 * At Rest (v=0) (a=0)
 * Constant (--> --> -->) (a=0)
 * Increasing (-> --> --->) (a -> a)
 * Decreasing ( ---> --> ->) (a <- a)
 * d-t
 * At Rest -a horizontal line
 * Constant- linear line steeper slope=higher velocity
 * Increasing- A curved line- going up is going away from origin, going down is going in the opposite direction.
 * Decreasing- goes from big slope to small slope
 * v-t
 * At Rest- a horizontal line on the x axis
 * Constant- a horizontal line anywhere but on the x axis negatives are in the opposite direction.
 * Increasing- a linear line that goes away from the x axis slope = acceleration
 * Decreasing- a linear line that goes towards zero

__** At Home **__

>> >> === ===
 * __**Free Fall and the Acceleration of Gravity**__
 * Free falling objects are objects that are only affected by gravity, so no air resistance is being acted upon them. Objects in free fall accelerate at a rate of 9.8 m/s/s. At ticket tape diagram can chow the acceleration. The acceleration due to gravity is called acceleration of gravity and it is not limited to downward falling. Gravity will always affect am object even when velocity is zero. The symbol to represent it is g.
 * In a position versus time graph the curve starts out shallow then becomes steep. On a velocity versus time graph, the line begins at zero and has a negative slope of 9.8 m/s/s. Th equation to find the velocity of a free falling object is V f ﻿=g*t. To find the distance, use the formula d = 0.5 * g * t2
 * Most people would assume that objects of different masses have different rates of free fall, but that is false. The reason people believe this is due to observations they have made in the physical world.
 * __**Describing Motion with Equations**__
 * Movement of an object is associated with several factors, such as time, speed, displacement, and acceleration. In most cases, not all the information is known. In these instances, kinetic equations can be used. There are four equations that can be used and each has four variables that can be applied to it.
 * [[image:http://www.physicsclassroom.com/Class/1DKin/U1L6a1.gif]]
 * The symbols are, v i stands for initial velocity, v f ﻿stands for final velocity, a stands for acceleration, d stands for displacement, and t stands for time.
 * To solve equations, identify what needs to be found and what variables you have, then pick the appropriate equation, plug in and solve.
 * With a free fall problem, the velocity can be assumed to be -9.8 m/s/s. If the object was dropped, then the initial velocity is 0.

[]



= Day 3﻿ =

**Lesson 5 - Newton's First Law**
**__In Class__**


 * **Inertia**
 * The tendency to continue to do what your doing.
 * An object will stay at rest
 * An object will stay in motion
 * At constant speed
 * In a straight line
 * Unless forced to do otherwise
 * Static Equilibrium
 * Object at rest
 * v=0 a=0
 * Forces are balanced
 * Dynamic Equlibrium
 * Object in motion
 * Constant speed
 * Straight line
 * v does not = 0 a=0
 * **Mechanical Forces**
 * Units are Newtons (N)
 * Push or pull
 * External to the system/object
 * Cannot be transferred or carried
 * Four Types
 * Weight
 * Symbols w, F g
 * Pull of earth on mass
 * Points down
 * w=m*g
 * m is in kg
 * g is 9.8 m/s/s
 * Friction
 * Symbols f, F f
 * 2 surfaces rubbing together
 * Parallel to surface
 * Opposite direction of motion
 * f=µN
 * Normal
 * Symbols N, F N
 * Support force
 * Wherever 2 surfaces touch
 * Perpendicular to the surface and through system
 * Tension
 * Symbols T, F T
 * Rope or chain
 * Only a pulling force
 * Runs along the rope or chain
 * Away from an object

**__At Home__**


 * ** Newton's First Law of Motion **
 * The first law is also called the law of inertia. Inertia is the object's resistance to changes in motion. Inertia depends on the mass, the greater the mass, the greater the inertia. The first law states that an objects velocity does not change unless acted upon by an outside force, this means that objects tend to continue to due what they due unless acted upon. The law can be observed in everyday life with liquids and how their want to keep moving in a direction causes it to splash in its container.
 * Before this idea, the common thought was that all objects wanted to come to an at rest position and force would be required to move it. Galileo said that an object will go to rest due to friction. Newton expanded the idea by saying that an object stops due to the friction force, so without it an object will continue to move.
 * It can be also said that inertia is resisting of changes in its velocity, or resistance to acceleration. So, objects moving one way will continue to move in the same path. According to this law, objects must be acted upon by an unbalanced force.
 * There are different types of forces that can act upon an object. One is the force supporting the object, called a normal force. another force is the force of gravity. When these two forces are in opposite directions, then the net force tends to be zero in other words, the object is at equilibrium. Another force is friction force that goes in the opposite direction from the object's movement.

Joke " When a third grader was asked to cite Newton's first law, she said, "Bodies in motion remain in motion, and bodies at rest stay in bed unless their mothers call them to get up"

**Lesson 6 - Newton** **Diagram**
__** In Class **__


 * ** Newton's Second Law Lab **
 * Objective: What is the relation between
 * Net force and acceleration?
 * Mass of an object and it's acceleration?
 * Hypothesis:
 * Net force and acceleration is directly proportional. The graph will be a linear line with a positive slope.
 * Mass and acceleration is inversely proportional.
 * Reasoning
 * More force on an object causes it to accelerate.
 * It will take more force to accelerate an object of greater mass than one with lesser mass to the same acceleration rate.
 * Data
 * [[image:Lab3-1-data.PNG]]
 * [[image:Lab3-2-data.PNG]]
 * Graph
 * [[image:Lab3-1-graph.PNG width="542" height="351"]]
 * [[image:Lab3-2-graph.PNG width="554" height="380"]]
 * Analysis
 * Net force and acceleration are directly proportional. The y intercept is the friction force witch was .0313 newtons. The slope is the mass of the object and from the equation it can be seen that the the weight is .545 kg, when it actually was .53 kg. The deviation is due to the friction force acting on the pulley. The error came out to be 2.9% error. The y value represents the net force and x value represent the acceleration
 * Acceleration and the mass are inversely proportional. The negative exponent means that the net force is divided by the mass. The slope is .2284 and is supposed to represent the net force, which is .294, and the exponent to the x or mass value is supposed to be -1 not -1.228. The error was 22.2%. The great error is due to the greater amount of friction acted upon objects of greater mass, so when the mass was larger, friction slowed the acceleration down.
 * [[file:Lab3.xlsx]]

At Home


 * Force and it's Representation
 * Force is a push or pull acted upon an object by another object. Forces are either due to direct contact or at a distance. Contact forces are frictional forces, tensional forces, normal forces, air resistance forces, and applied forces. Distance forces are electrical, magnetic and gravity. A force is a vector quantity with the unit of 1 kg * m/s. Forces must be descibed by both direction and strength of forces.
 * Forces can be and represented by the diagram bellow. The diagram is a free body diagram. These types of diagrams can have more than two vectors. The diagram shows that the forces are equal so there is no net change and it is a balanced force. For there to be an unbalanced force, a new vector has to be added or the magnitudes have to change. To determine the net force, you need to add the vectors going in the same direction while subtracting the the vectors in the opposite direction.
 * [[image:http://www.physicsclassroom.com/Class/newtlaws/u2l2a4.gif]]
 * Applied force is the force a person applies or an object on to another object. Gravity force is the gravitational pull the earth has on an object's mass. Mass and weight are not the same. Normal force is the force supporting an object. Friction force is the force created by two objects rubbing against each other. Air resistance is a friction force acting upon a falling object. Tension force is a pull exerted through a rope or chain. A spring force is a stretch or compression acted upon an object by a spring.

=Day 4=

** Lesson 7 **
__** In class **__


 * ** Drop and Pull system **
 * Acceleration min. = 0 m/s/s
 * Acceleration max. = 9.8 m/s/s
 * Acceleration = (m Hanging * g)/(m Hanging + m cart )
 * If m Hangin = m cart then a = 1/2 g
 * If m Hanging > m cart then a > 1/2 g
 * If m Hanging < m cart then a < 1/2 g
 * ** Forces **
 * At equilibrium acceleration = 0 = net force
 * Net forces can only be calculate over one plane

** Lesson 8 **

 * In Class **


 * ** Friction **
 * No idea what causes it
 * Surfaces are not smooth
 * Different surfaces react differently to different surfaces
 * Coefficient of friction
 * Number that stands for how two surfaces react with each other
 * Should be between 0-1
 * Few exceptions
 * Not the friction force
 * Symbol is the Greek m
 * No units
 * Ratio of friction force over the normal force of the surface
 * ** Lab **
 * locations || Average coefficient ||
 * Gym floor || .286 ||
 * Concrete || .486 ||
 * Floor Tile || .278 ||
 * Tabletop || .205 ||
 * Carpet || .42 ||
 * Pavers || .358 ||
 * The average coefficient shows the different frictions an object had. The higher the coefficient, the higher the friction.

__** At Home **__


 * Objects will only accelerate if there is a net force or an unbalanced force on an object. The acceleration of an object is directly proportional to its net force and inversely to its mass. So, as the net force increases acceleration increases, and as mass increases, acceleration decreases. The equation is acceleration is equal to the net force over the mass in kg. Acceleration only deals with net force. The unit for net force is newton and 1 newton equals 1 kg*m/s/s.
 * It is important not only to know and use newtons law, but to also believe in what they say. People going into physics tend to not want to change their mind. It is for the best to become aware of other ideas, evaluate them and keep the more rational one. One of the biggest mistake is that for continual motion to happen, there needs to be continual force.
 * Net force is equal to mass times acceleration, which is equal to the sum of vectors in the same direction minus the sum of the vectors in the opposite direction.

=**Day 5**=

**Lesson 9**
__**In Class**__


 * ** Air resistance **
 * Falling objects are affected by air if they are affected high enough.
 * The high speeds of the object causes air particles get caught under it causing a cushion.
 * The longer an object falls the greater the air resistance.
 * When air resistance equals the gravity it stops accelerating and is called terminal velocity.
 * F=ma
 * Force of air resistance - weight = mass * acceleration
 * When the left side = 0, terminal velocity is reached
 * Resistance is proportional to the terminal velocity squared
 * When a parachute opens velocity decreases
 * when chute is maxed out in the particles it has the acceleration up slows down to 0
 * It goes back to terminal velocity
 * ** Newton's third law **
 * Every action has an equal and opposite reaction
 * Contact between two things touch each other back
 * The force exerted on one, is exerted on the other.
 * All forces come in pairs, that equal in size, point in opposite directions, acting on2 separate systems
 * The moon exerts an equal force on the earth as the earth on the moon


 * ** Lab **
 * Question: How much hanging weight in a drop pulley system is necessary to cause a .5 kg cart to move .8 meters in .85 seconds?
 * Calculations
 * d=v i *t+(1/2)*a*t^2
 * .8=(0)*.85+(1/2)*a*(.85)^2
 * .8=.36125*a
 * a=2.21 (m/s/s)
 * a=(m H *g)/(m H +m Cart )
 * m H Stands for m Hanging
 * 2.21=(m H *9.8)/(m H +.5)
 * 2.21m H +1.105=9.8m H
 * 1.105=7.59m H
 * m H =.146 (kg)
 * Data Collection
 * Trial 1: .89 (s)
 * Trial 2: .856 (s)
 * Trial 3: .829 (s)
 * Average:
 * (.89+.856+.829)/3
 * 2.5753/3
 * .858 (s)
 * Percent Error
 * abs(t experimental - t theoretical )/t theoretical * 100%
 * abs(.858-.85)/.85 * 100%
 * .008/.85 *100%
 * .9%
 * Results
 * The time the group got was very close to the desired time, less than 1% off. The percent error could be due to the addition of the picketed fence adding more weight to the cart and the cart not starting at an initial velocity of zero.

__** At Home **__


 * All objects accelerate towards the earth at the same rate no matter what the mass of the object, the only difference is, is that objects with less mass will have less force than a more massive object, due to gravity affecting larger mass more than smaller masses. All free falling objects meet air resistance. This occurs due to the area of an object being repelled by the air. The greater the surface area, the greater the air resistance. All free falling object, if given enough time, reach terminal velocity, the point were the speed of an object in free fall does not increase. This is due to the acceleration of gravity is equaling out to the air resistance. Objects with greater mass have terminal velocity at higher speeds.
 * Forces are the result of interaction. When to objects interact, they exert the same amount of force on each other. an object experiences an equal force exerted on it as it exerts on another object. All iterations between objects come in pairs.
 * [|Video]explaining air resistance.



**Lesson 10**
__**In Class**__


 * **Know Angle + Velocity**
 * Velocity of x equals initial velocity times cosine angle
 * Velocity of y equals initial velocity times sine angle
 * **Know Velocity of x and y**
 * Velocity equals the square root of y velocity squared plus the x velocity squared
 * Angle equals the inverse tangent of velocity of y over velocity of x

__**At Home**__

>
 * **Vectors: Fundamentals and Operations**
 * Vectors must be labeled with a clear direction and magnitude (Shown Below). The direction of vectors can be stated in many ways, but their magnitude must be to scale.
 * [[image:a1.PNG]]
 * Normally, when adding vectors, vectors in the opposite direction are subtracted and vectors in the same direction are added, but vectors on a slant differ. Vectors can be broken up into two components, the x vector and y vector. The two vectors creat a triangle withe the original vector being the hypotenuse. If you have two sides then you can use the Pythagorean theorem to solve for the hypotenuse. If you have the hypotenuse and angle then trigonometry must be used.
 * [|http://www.cs.utah.edu/~draperg/cartoons/jb/vector.html]