Sunday, February 21, 2010

The Conservation of Energy!

Part A:
This is what I learned about the Conservation of Energy.  When we were first introduced to energy we asked, "What is energy?"  Well to be honest I found that question very hard to answer.  I sat in my seat and thought about electricity, springs, elastics, fuel, and my favorite, food.  I asked, "What do all of these things have in common?"  Well we later learned that energy is the potential to "do work."  For example:  By lifting weights the energy I use from my food intake is used to lift the weight and therefore give it potential energy due to its height in relation to a reference point that can be the ground, or where the weight started.  The energy I put on the weight did not disappear, in fact, energy never disappears in our universe.  The energy actually it is transferred into another form, this being kinetic (motion), elastic (spring or stretching related), potential (in relation to a specific height), or internal (as in various forms of friction that can lead to heat).  Energy can be stored in different forms, but it can never disappear.  Although by the end of my work out I am very tired and energy depleted, the energy I have lost has actually only been transported to other forms around me.  This concept is useful while we solve problems that are asking about energy.  We can set up equations to find the quantity of various forms of energy at different periods of time in Joules (Newtons x meters).  This quantity represents "work" which can be found by finding the product of Force (N) and distance (m).  The work that is done happens over a period of time, which gives us a rate of work accomplished, which is known as power.  The unit of power is Nm/time (Watts - W).  What I really enjoy about energy is that the quantitative value of energy is constant throughout the situation.  When we began we made energy charts where we were required to identify the system and show where all of the energy dissipated.  After grasping this concept options of problems we can solve become infinite with the simple concept that the original energy will be present in the final result.  Since Joules is a universal unit it can be easily tracked throughout the problem.  

Originally when we began studying the concept of the conservation of energy I had a hard time interpreting and drawing qualitative graphs of energy problems.  Part of my problem was that I did not originally understand what each form of energy really was.  Through out the "clicker quiz," the class work, and our Physics Quest, I was especially able to grasp the concepts through contemplation.  The process was not easy and that Physics Quest took much more time than it would take me now, but now I go into problems with a more open mind and consider any possible transfer of energy.  Our Physics Quest had several difficult problems that cause me to create a checklist of different forms of energy.  This technique has helped me tremendously, and I would recommend it to all of you!  If you go down the line of different forms of energy in your head, it will be much easier to understand the problem, and you will make far fewer mistakes.

My problem-solving skills have continued to improve.  I have been more "snappy" toward understanding how to set equations equal to each other and have items cancel out.  This has been especially important in this unit because we have the constant variable that is the energy that never leaves the system.  This forces us to work while setting the original energies equal to find the current states of energy.  Once I understood the qualitative concepts of energy, the quantitative was very natural. 

Part B:
An example of how our energy knowledge is applied to our everyday life can be found while watching many of the winter sports on TV.  A great example of this was while Shaun White, an American half pipe expert, completed his two runs.  The start of the half pipe is uphill which gives him potential energy due to gravity, his mass, and height.  Shaun White left the start and proceeded down hill, gaining Kinetic energy.  As he changed elevations during his jumps his Kinetic energy and potential energy changed, but the sum of the energy remained constant.  His board made friction with the snow and left Internal energy.  We know that the total energy of the system was constant throughout each of his runs, although it was constantly changing states. 

Wednesday, February 3, 2010

FINAL PROJECT


How can we apply physics to a
bike that is making a turn on a flat track verus a banked track?



I appreciate all comments!  Thanks to all who helped make this release better!  I took your comments into consideration and made significant changes to my project.


Notice that at one moment in time the friction is static!  Therefore we can use static "MU's."

Tuesday, February 2, 2010

Eric's Physics Project over Bikes







How can we apply physics to a
bike that is making a turn on a flat track verus a banked track?



I appreciate all comments!  Thanks to all who helped make this release better!  I took your comments into consideration and made significant changes to my project.


Notice that at one moment in time the friction is static!  Therefore we can use static "MU's."

Monday, February 1, 2010

Project Over Dynamics Embed

Project Over Dynamics

http://prezi.com/yqfewccn5th-/edit/#360

Attributions

http://www.icteachers.co.uk/children/sats/images/gravity.gif


http://d3f8w3yx9w99q2.cloudfront.net/1268/hampton-fitness-55-100-lbs-dura-bell-dumbbells-set-dumbbells/hampton-fitness-55-100-lbs-dura-bell-dumbbells-set-dumbbells_0_0.jpg

http://www.diverse-group.com/page1/files/mac-os-x10-5-leopard_1.jpg

http://images.google.com/imgres?imgurl=http://upload.wikimedia.org/wikipedia/commons/4/4c/Studded_tires.jpg&imgrefurl=http://commons.wikimedia.org/wiki/File:Studded_tires.jpg&usg=__HgDh3PyCaosNhcwVLF7jdK0GsVM=&h=1268&w=1312&sz=306&hl=en&start=16&um=1&tbnid=Hyz8Y3bksEQk7M:&tbnh=145&tbnw=150&prev=/images%3Fq%3Dbike%2Btires%26hl%3Den%26client%3Dsafari%26rls%3Den%26um%3D1

http://en.wikipedia.org/wiki/Friction

http://motoaus.com/images/stories/ducati2008/xaus-hypermotard.jpg

http://3.bp.blogspot.com/_g3_LbRMsQYc/SxGnHNy7gyI/AAAAAAAAEa0/qG1E63d8tO8/s1600/400px-Greek_lc_mu.svg.png

http://images.askmen.com/blogs/sports/lance-armstrong-the-best-ever.jpg

http://www.physicsclassroom.com/Class/Newtlaws/u2l2c1.gif

http://www.bikeradar.com/gear/article/lance-armstrongs-trek-madone-69-livestrong-20045

http://www.examiner.com/x-14380-NY-Celebrity-Fitness-and-Health-Examiner~y2009m7d20-Lance-Armstrong-vs-Alberto-Contador-Is-body-weight-a-factor

http://www.google.com/search?client=safari&rls=en&q=165+lbs+to+kg&ie=UTF-8&oe=UTF-8

http://blog.newsok.com/gossip/files/2009/02/lance-armstrong.jpg

http://img2.timeinc.net/people/i/2004/04/weekinphotos/040802/larmstrong.jpg

http://www.youtube.com/watch?v=Bg1ymKYuWak

http://tell.fll.purdue.edu/JapanProj/FLClipart/Adjectives/fast.gif

http://upload.wikimedia.org/wikipedia/commons/9/97/Centripetal_force.PNG

http://scrapetv.com/News/News%20Pages/Business/images-2/Billy-Mays-pointing.jpg

http://www.trekbikes.com/us/en/bikes/road/madone/madone69/

http://www.bookshelfboyfriend.com/uploaded_images/fullsize/301bike-wheel-diagram.jpg

http://zenwerx.com/pi.png

http://cdn.mos.bikeradar.com/images/news/2009/01/21/1232542708618-n89r7gk8ypak-850-65.jpg

http://www.driversedguru.com/wp-content/gallery/auto-accessories/tire-pressure-valve-caps.jpg



http://faithfulfiend.files.wordpress.com/2009/03/lance-armstrong-kaws-trek-road-bike.jpg



http://prezi.com/yqfewccn5th-/edit/#58

http://weblogs.cltv.com/news/weather/traffic/armstrong-contador_1440595c.jpg

http://road.bike198.com/wp-content/uploads/2009/12/lance-armstrong.jpg

http://nimg.sulekha.com/sports/thumbnailfull/lance-armstrong-2009-8-15-14-43-20.jpg

http://www.singletracks.com/blog/wp-content/uploads/2008/11/lance-armstrong.jpg

http://dunningrb.files.wordpress.com/2009/01/cycling_tour_de_france_tdf1075z7.jpg

Wednesday, January 27, 2010

Circular Motion and Gravitation Reflection

This is what I learned about Circular Motion. Objects in circular motion have a constant velocity, or "Uniform Circular Motion." In these cases the objects are experiencing an inward or centripetal acceleration. Although the velocity's magnitude does not change it is accelerating because it is changing direction. The objects velocity at any given point is tangential. You can find a tangential line by drawing a line through the circle that only intercepts the circumference in the exact point of the object's location. The objects in circular motion move along the circumference or perimeter of the circle. The perimeter of a circle can be calculated by 2 pi R or pi D. The frequency is the number of full circular rotations per unit of time (s), also known as Hz, and the Period (T) is the time for the object to complete one entire rotation around the circle. In order to keep an object in a circular motion there must be an inward force.  This is also known as the "centripetal force requirement.” Commonly this force is friction, found by multiplying  Mu and Fn, the x component of tension, or gravity. The minimum force needed to keep an object in circular motion can be found by using the equation Fc=mv^2/r giving you units (N). You can find the centripetal acceleration by using the equation Ac=v^2/r giving you the units (m/s^2). In vertical circular motion the tension in the string or cable varies with the position of the object. At the highest point and lowest point in a circle you find the centripetal force that must equal (mv^2/r).  This can easily be found by drawing an FBD with an arrow showing the object's acceleration. Any force working with the acceleration is positive and any force moving in the opposite direction of the acceleration is negative.  Just as in problems involving torque, and systems you put the forces moving in the direction of the movement or acceleration as positive, and the forces moving in the opposite direction of the acceleration as negative.




This is what I learned about Universal Gravitation. Isaac Newton proposed an abstract theory that all masses attract each other, just as the earth attracts all objects in and outside of its atmosphere. He proposed "Every object in the universe attracts every other object in the universe (FG) with a force(G) that varies directly with the product of their masses(m1 and m2) and inversely with the square of the distance between the centers of the two masses(r^2)." This gives us the primitive equation Fg=Gm1m2/r^2 that can be manipulated to solve for any item in the equation. The "G" in the equation has been calculated by Cavendish as 6.67e-11 (N.m^2/kg^2).

What I have found difficult about what I have studied is setting up equations where you have masses and variables that "cancel out." This is something that some people have an eye for, but I am learning to recognize these occurrences in common circumstances. I have learned what the source of gravity is, and how planets, satellites, and moons are in a constant state of "freefall." I think that by learning circular movement I now better understand frictional force.

My problem-solving skills have become better in recent weeks. Some problems in our homework assignments and recent flying pig and "Holy Cow" labs have really made me realize the power of physics. I have tested myself by thinking about problems constantly as I go through my normal daily routine. While going through my day I sometimes think back to the problem that puzzled me earlier. By helping other students with problems and asking for help on assignments I think that our class community has done a good job helping each other grasp concepts.  I think that I could take advantage of our wiki more and get feedback from more than just the one friend I call, and at the same time, help the entire class better learn or be exposed to a concept in a new way.