Additionally the Following Are Helpful

These notes are to supplement the reading of Chapter two pages 38-69 in the Holt Text Physics Text Book by Serway and Faughn.

Additionally the following are helpful. - The moving man demo at http://phet.colorado.edu/simulations/sims.php?sim=The_Moving_Man

- The kinematics web demos at http://www.mrwaynesclass.com/teacher/index.html#kinematics

- Graph that motion at http://www.physicsclassroom.com/shwave/graphthat.cfm use in conjunction with the worksheet at http://www.physicsclassroom.com/shwave/gtmintro.cfm

- Good description of most topics here http://www.physicsclassroom.com/Class/1DKin/

- Click on 1-D kinematics for helpful flash videos http://www.physicsclassroom.com/mmedia/

- You tube on special Relativity http://www.youtube.com/watch?v=Ux-YD8Ky1hs http://www.youtube.com/watch?v=6rl3Z9yCTn8 http://www.youtube.com/watch?v=WgsKlSnUO0k http://www.youtube.com/watch?v=W6o_-yTa168

- Vel and accel explained http://www.youtube.com/watch?v=ZrRSc3aKABk Note they are using “s” for displacement, this is not done much anymore, most people use” d” or “x”

VA SOL’s covered: PH.2 The student will investigate and understand how to analyze and interpret data. Key concepts include a) a description of a physical problem is translated into a mathematical statement in order to find a solution; b) relationships between physical quantities are determined using the shape of a curve passing through experimentally obtained data; c) the slope of a linear relationship is calculated and includes appropriate units; d) interpolated, extrapolated, and analyzed trends are used to make predictions; and e) analysis of systems employs vector quantities utilizing trigonometric and graphical methods. PH.3 The student will investigate and understand how to demonstrate scientific reasoning and logic. Key concepts include a) analysis of scientific sources to develop and refine research hypotheses; b) analysis of how science explains and predicts relationships; c) evaluation of evidence for scientific theories; d) examination of how new discoveries result in modification of existing theories or establishment of new paradigms; and e) construction and defense of a scientific viewpoint (the nature of science).

PH.4 The student will investigate and understand how applications of physics affect the world. Key concepts include a) examples from the real world; and

PH.5 The student will investigate and understand the interrelationships among mass, distance, force, and time through mathematical and experimental processes. Key concepts include a) linear motion; PH.14 The student will investigate and understand that extremely large and extremely small quantities are not necessarily described by the same laws as those studied in Newtonian physics. Key concepts include e) relativity; 1 Dimensional Motion

Displacement ( please note the text book uses an “x” for displacement, I will use a “d”) - Displacement is the net distance travelled along with the direction, calculated

by subtracting the final position from the initial. d=xf-xi - Because it has both magnitude and direction it is called a vector. - Often this is the same as the distance traveled, but it does not have to be. - Examples (Imagine a car driving on a number line.) o A car starts at position 0m, then travels to position 100m. In this case both the distance and displacement are 100m. o A car starts at position 100m and travels to position 0m. In this case the distance is 100m but the displacement is -100m because the final position (0m) – initial position (100m) = -100m o A car starts at 0m travels to 100m and then back to 0m. In this case the distance is 200m but the displacement is 0m - 0m= 0m

Velocity - velocity is a speed w/ a direction. - called a vector (+ forward/up, - backward/down) - v=d/t velocity= displacement/ time - SI unit: m/s

- v = (vf +vi)/2 - both are avg. vel., shown w/ bar

Acceleration - Is a change in velocity

- a=Dv/ Dt a= (vf -vi)/t - D is the Greek letter “delta,” we use it to mean “a change in” 2 - SI unit is the m/s - when your speedometer moves you are accelerating - Also is a vector

Steps to solving a problem - Step 1 Read the entire question word for word without writing. - Step 2 Sketch the diagram of what is happening. - Step 3 Make a list of all the given information include symbols and units. - Step 4 Identify what you are looking for and list it with a “?” - Step 5 Write down any equation that applies. - Step 6 Use the list to put numbers into the equation and solve. - Step 7 Write down your answer w/ units and circle it. - Step 8 Check to see if you answer is reasonable. Example Problem - If a car is going 20m/s for 10s, how far will it travel?

V=20m/s t=10s d=?

- Two types of graphs.  Position (Displacement) vs. time • The slope (rise/run) equals the velocity  Velocity vs. time • The slope (rise/run) equals the acceleration

Position VS. Time graphs

Who is not moving? Who is moving at a constant velocity? Who has the fastest instantaneous velocity? Describe Carol’s motion. What is Norman’s average velocity from 2-20s?

Velocity vs. time graphs

A horizontal line on a velocity vs. time graph indicates constant velocity, (or moving at a constant speed.) The higher the line is the faster the movment is. Here blue is going faster than red. Both have a positve velocity because they are above the x-axis. Green however is below the x-axis, this means that the velocity is negative, or in other words the green movment is in the oposite direction of the red and blue. A slanted line on a velocity vs. time graph indicates constant acceleration. The slope is the acceleration. Therefore, the red line has a negative acceleration, while the green and blue lines both have a positive acceleration. When the red line crosses the x-axis it is stopped and changing directions. The red line could be the graph of a ball that is rolled up a ramp, then rolls back down. Which people stop and when? Who is most likely on a moving sidewalk? Who is speeding up the whole time? Describe Mike’s motion. How fast is Holly going at 2s? . . . 15s? What is Mary’s average acceleration from 2 seconds to 20 seconds?

Aristotle to Galileo notes. Greek Culture was the most influential - other cultures had discoveries, but didn’t spread EX, China and Mayans - good roads, common language, good sail boats and trade routes lead to the spreading of ideas from Greece.

Socrates - argued against Greek Gods in control. - was called “Gad fly” - influenced mostly kids - was put on trial for corruption of minors—put to death (poison) - Plato his best student was at the execution and wrote about it.

Plato – w/o Gods in control he looked for other ways things worked - truth was found in meditation and thinking - Allegory of the cave - Most of work was in philosophy, ethics, government, and music but he did come up with 4 elements. - Thought outer space was perfect unchangeable –all things orbit the earth. - Started academy lasted 200 years.

Aristotle- Plato’s students adopted his ideas, but added observation to thinking. - Very good in biology- first to dissect—dad was a doctor - Explained inductive (probable inferences- interpolation & extrapolation) and deductive reasoning ( if this is true- what are consequences. Einstein next person to significantly use in science - Said 4 elements earth, fire, water air, - were made of hot/cold, wet/dry. Had to balance chem. Vol. Represented by a3, b3, a2b,ba2 - Everything had a natural place - When earth fell it returned to its natural place at rest on the ground. - Things fell with constant velocity - Heavy thing fell faster - Violent motion was any motion that was not natural- required a force. - Speed is proportional to the force for violent motion. - Made a fifth element, aether, (outer space) circular motion was natural - Outer space was believe to be perfect and unchangeable. - school was lyceum - Taught Al the Great For the next 2000 years Aristotle and the Church where the authority Then came Galileo Galilei around 1600

Galileo- called father of science - started to do experimentation - father wanted to be a doctor – went to college and discovered math - figured out the pendulum by watching chandeliers in Church - greatly improved telescope (although he did not invent it) first to use it to look at sky. - First to see mountains on moon, sun spots, phases of Venus, and moons of Jupiter- called Galleon moons - Published in book (Latin) Starry Messenger—lead to problems - Moons of Jupiter showed that all does not orbit earth - Phases of Venus show it orbits the Sun - Sun spots – outer space is change able - Mountains on moon – not perfect sphere - Wrote a second book in Italian “Discourse on two Chief World Systems” - simplicito, sogredo, and this book made church and Aristotle look foolish - Was called in to be inquisition and threaten with torture. - Forced to recant his beliefs and placed on house arrest for the rest of his life (9yrs) - Altho didn’t agree with church view still believed in God- two daughters were nuns. - Wrote third book while on house arrest 2 new sciences (continued to work in house,) came up with formulas - Ramp with even spaced marks, ball rolls odd number same amount of time, used water clock to measure time. - Total distance to then is time squared 2 2 2 - d=vIt+½ at vf =vI + at vf =vi +2ad - assumes no wind friction - Thumb is preserved in Museum of the History of Science - Pope John Paul II apologized for mistake in 1990

- If gravity is constant acell what is the number. Galileo used increasing slopes to predict 90 (which he could not measure) 2 2 - g = -9.8m/s on earth (32ft/s ) - slightly higher in death valley, slightly less on mountains.

 Because the acceleration due to gravity is constant, the velocity that an object is tossed up with will be the same velocity that the object has when it falls back to the same height that it was tossed up from, only with the opposite sign of course.  v (up) = -v(down) therefore bullets shot up !!! bad!!!

Example problem A football quarterback intentionally grounds the ball by throwing it straight downward with a velocity of -12m/s. What velocity will the football have just before it hits the ground 1.8m below?

List Formula

Vi= -12m/s 2 2 d= -1.8m vf =vi + 2ad a= -9.8 m/s2 2 2 2 vf=? vf = (-12m/s) + 2 (-9.8m/s ) (-1.8m)

vf = vf= -13.4m/s

Note: The displacement is negative because the ball moved in the negative direction. The software would not allow me to put the units under the radical (square root) properly, so I left them off. Finally, Mathematically when you take a square root, you get two answers (one positive and one negative) it is up the person to choose the proper one. Here we chose negative because the ball would be going down. Special Relativity

- In 1905 Albert Einstein wrote three papers, two of which earned him Nobel Prizes (one for Brownian motion, the other for the photoelectric effect.) It was, however the other paper (the one on special relativity) that is best remembered and the focus of this section. - In Einstein’s Special Relativity paper he borrowed from Lorentz, Michelson and Morley, Maxwell and others. He put together the work they had done and explained it in a simple way that encompassed many theories and experiments of others. - Instead of performing experiments as evidence for his theory, he instead used deductive reasoning, where he stated things he felt were true and then explains what the consequences are if they are true. The statements he started with are called postulates. - 1st Postulate (Collins Paraphrased) – The Laws of Physics’ are the same and work for everybody, no matter where you happen to be standing or how fast you are moving. - 2nd Postulate (Collins Paraphrased) – The speed of light is the same for everybody, no matter where you happen to be standing or how fast you are moving.

- Thought experiment: Einstein said imagine a person on train that is moving at a constant velocity. If were to bounce a beam of light from the floor to the ceiling and back to the floor of the train. The light from his perspective would have travelled twice the height of the train. However, for a person who is stationary watching this from the side of the train they would see the light move at a diagonal, therefore travelling a greater distance. Since the speed of light is the same for both people, the length of object in motion must be shorter than at rest. Furthermore, since d=vt and the speed of light is constant, if the length is different the time it takes must also be different.

- Deductions: For slow speeds, the difference is too small to notice, but as speeds approach the speed of light the difference get larger.

- Time Dilation – Time advances slower for an object in motion relative to objects at rest. For, example (twin paradox) two brothers, who are twins are the same age. One brother boards a ship and travels at speeds close to the speed of light, relative to the brother that stayed home. When the travelling brother returns, he has aged much less than the twin who did not travel.

- Where - t is the time measured by the stationary observer - t’ is the time measured while in motion

- is the relative velocity between the observer and the moving object,

- is the speed of light,

- Length Contraction - The length of objects gets shorter relative to their stationary length.

- Where - L is the proper length (the length of the object in its rest frame), - L' is the length observed by an observer in relative motion with respect to the object,

- is the relative velocity between the observer and the moving object, - is the speed of light,