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Sarah's Physics 111 by
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# Sarah's Physics 111

## Linear Motion

### displacement

difference between point A and point B, no matter the route taken to get between the two.

### speed

Difference between distance traveled and time.

motion diagrams, loggerpro, videos, graphs, temporary hatered equal to the heat of a thousand suns...

s=d/t

similar to velocity, but direction makes no difference. Simply the rate of motion.

### velocity

any change in speed and or direction of travel

cop v. perp, motion graphs, position graphs, velocity graphs, VPython, SWEET!(but not easy at all...), assignment #6 and 7 a total bust!, In week 4 I have not been able to get my VPython projects to do anything at all! All I seem to get is a syntax error and since Im not familiar with code writing at all I am having an exceddingly difficult time figuring out what I did wrong. To say the least, Im frustrated. I sent out an email asking for help, we will see if I can get it fixed.

depends on rate of motion and direction, v=d/t, in physics, a negitive number usually denotes direction. This is helful with velocity.

### newton's laws of motion

1st law, An object in motion will stay in motion until acted on by an unbalaced force. An object at rest will stay at rest until acted on by an unbalanced force., Imagine we are in space floating but not moving at all. We will not go anywhere until an outside force is exerted on one of us. Motion doesn't spontaneously appear. If I push you, you will begin moving away from me continuously until something stops you. Since we are in space, that isn't likely to happen anytime soon, especially without gravity or friction.

2nd law, F=MA, This law explaines why it takes more force to move an object with greater mass than one with a smaller mass. Acceleration is the force exerted on an object divided by the mass of it. If you exert 10 N of force on an object with 1 kg of mass, it will have an acceleration of 10m/s/s. If you exert the same 10N on an object with 10kg of mass, it only moves with an acceleration of 1m/s/s.

3rd law, for every action there is an opposite and equal reaction., In our P1 and P2 projects, our launchers used this rule to launch our mallows. While the mallows were in flight, the earth was pulling on them with the same force the mallows were pulling up on the earth. Even though the two objects have a tremendous difference in mass, they are still exerting the same amount of force on each other.

### acceleration

F=ma

different from velocity because acceleration is the change in rate or in other words, velocity is going somewhere at a certain rate, acceleration is how fast are you speeding up. You can have velocity without acceleration, but you cant have acceleration without velocity., i.e. If you drive onto a freeway, you will have a velocity because you are traveling in any given direction at a given speed. You will also have acceleration as you press the gas to continuously speed up to 65mph, your rate of speed increases. After you get to 65mph, you put on the cruise control to maintain that. You now have a constant velocity, but no acceleration.

## Outline

### Non-linear Motion

3D motion, Launcher problem, totally got it! pencast made it clear. understanding the relationships between values makes it easy to apply the same rules and principals to a completely different question., x,y,z axis, must be viewed as 2 or 3 different problems and combined to get motion in all three dimensions.

2D motion, only uses the x and y axis, during launch, flight and landing of mallows, the two axis can tell you not only how fast and how far the mallow moved along the x axis, but can also tell you how long it will be in the air after taking into concideration gravity's effect on the y axis.

Linear motion, x or y axis only, motion is only scrutinized along one direction. This is often used for the dreaded, "If a train leaves Denver...." velocity problems.

circular motion, Fc=m(v^2/r), I can use this equation, but I hope next week a pencast will make it seem more logical and natural to use., Ac=v^2/r, again, I can use it but I dont feel as comfortable with it as I would like. I did however see the relationship between the force and acceleration., maybe I just plain missed it, but how do I find the velocity and the arc??? pencast please!

### Forces and Momentum

Types of energy, Kinetic, Kinetic energy is the work required to give an object motion. This is often the result of transformed potential energy., i.e. pushing a car down a hill, the work required to get it moving is transformed into kinetic energy and is apparent when the car begins to move, Potential, potential energy is the energy stored within a system that is able to do work. This is usually transformed into kinetic energy or gravitational energy., i.e. Holding a book above a table stores the energy needed to make the book fall to the table if you let it go., Gravitational, 9.8 m/s/s, constant energy force that comes from earth's pull on all objects.

## Competencies

### Effectively communicate qualitative and quantitative information orally and in writing.

Even with the very easy concepts we worked on this week writing out explanations helps you to make more sense of it for yourself.  This I think will pay off big time later even though I am sure it will frustrate me as well.

## Frustrations!!!...and a few cool things.

### so much technology

LoggerPro

mindmeister, cool, but I wasnt sure at first what it might help. In the last week or so as the concepts really click, I find my map is much more detailed and I have a much easier time figuring out what to put in it. This week has been much more substance instead of reaction., on the down side, the more complex my map gets, the more problems Im having. It is slow and doesnt always save the last entry...Grrrr.

glogster, week 1, week 2, week 3, week 4, week 5, week 6, week 7, week 8, P1 glog, P2 glog, P3 glog

animoto, Marshmallow Launcher video, Intro video, love it, I will keep using it.

dipity, Ongoing project, interesting concept. I can see how it helps to see our work and progress, but I doubt I will continue to use it later.

VPython, 1st time using, I dont know the first thing about writing code so this was the hardest thing for me. Trying to understand the concepts and translate them to code I think only confused me more. I honestly didnt like it at all.

### organization

new accounts

thoughts, staying organized is really difficult for this class. since everything is digital and virtual and has to be interconnected I find myself second guessing everything and spending too much time double checking that everything is linked. I wish I had been able to come up with a better system.

time management, this was difficult for this class. I also had to take a chemistry class at the same time and combined with work I unfortunately had to do most of the work on the weekends. I hate waiting till the end like that but I didnt really have a choice this time. With that said, considering what I had to work around, I think I did pretty good. I wont take physics and chem at the same time ever again though...

## Projects

### Mallow Launcher

team, Melissa, team techie, google docs, logger pro analysis, writer, works sited, launch analysis, Norm, writer, conclusions, landing analysis, art director, logo, team name, Team Einsteins!, number cruncher, excel analysis, ME!, Editor, Final Glog, Revisions, rewrote physics section of final glog, Launch: During the launch portion of the motion Newton’s first and third laws are most apparent. His first law states that an object at rest will stay at rest until a (net) force is applied. The marshmallow remains at rest in the launcher’s bucket since the only force acting on it is the pull of earth and the launcher itself. Neither of these create a force strong enough to put the mallow in motion until the launching mechanism is triggered. At that time Newton’s third law comes into play. The force generated by the motion of the launcher is large enough to give the mallow motion but even so the marshmallow pushes just as hard against the launcher as it is leaving the bucket. For every action there is an equal and opposite reaction, even if the force and motion of one object causes the movement of the other. Both forces are instantaneous and perfectly equal. Flight: During flight, the marshmallow follows an arc shaped path. This movement involves all three of Newton’s laws. In regards to the first law, there is no force acting on the marshmallow in the X direction during flight so there is no change in acceleration. There is however a change in the Y direction because of the force of the earth pulling down on the marshmallow. As the mallow travels away from the earth in the first half of the flight there is negative acceleration since it slows down from the force of the earth overcoming the force of the launcher and the mallow’s mass (2nd law) pulling it in the earth’s direction. In the second half of the flight after it has reached the top of its arc and is traveling back to the earth it has positive acceleration. This is due to the increased (net) force in the direction of the earth due to the combined force of the earth and the mallow’s mass. Landing: During the landing phase the marshmallow goes from a state of increasing acceleration in a downward direction to a very sudden stop when it hits the ground. If in theory the marshmallow hit the ground once and stopped, it would have zero speed, velocity and acceleration. The only forces acting on it would be the force of the earth pulling down on it and the equal and opposite force of the mallow pushing down on the earth (3rd law). Since the earth’s mass is significantly larger, its’ force will continue to overcome the marshmallow’s force pushing back against it until a third force overcomes them both (2nd law)., Team Leader, Create timeline, Assign tasks, writer, flight analysis

plan, Everyone builds a launcher, best results is final project.

### Mallow Slingshot

Team, Sarah Contreras, My launcher was already a successful slingshot style., writer, editor, Johnsua Brindley, Converted to slingshot, writer, editor, Joshua Marriott, Also converted to slingshot style, writer, editor

Plan, Convert launchers into sling shots, use most successful for data, The Liberator was again successful, Rock it like noone's business!

### Paintball/ Bullet Motion

The Physics Kids

New Team Name, Same team mates

physics of motion, velocity, acceleration of bullet, rotational physics, momentum, exchange and transformation of energy

Colt .45, mass, velocity