conserve - Conservation of Energy Thermodynamics Total...

Info icon This preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
Conservation of Energy Thermodynamics Total Mechanical Energy Examples Thermodynamics Conservation of energy actually grows out of two main ideas in physics… the First and Second Laws of Thermodynamics. 1. “Energy can not be created or destroyed, only changed from one form to another.” This just basically means the if one thing loses energy, something else must be gaining energy. The opposite is also true. In an ideal situation this transfer of energy would be perfect and complete, but when was the last time you remember our universe being perfect…? This leads us to the second idea… 2. “In any energy conversion, there will always be some waste energy released as heat into the surrounding environment.” Because it is impossible to perfectly transfer energy from one form to another in the real universe, does that mean we are breaking the first law? No, in fact we recognize that the total energy can still be accounted for, it’s just that some of the energy is released as unusable heat. A large branch of physics called Thermodynamics studies the limits of just how close to perfect any device could be in transferring energy. There is a lot more to the laws of thermodynamics , but what you’ve just read are the basics that you need to know. Here’s an example of the two laws happening at the same time… According to the First Law , there is energy being changed from one form to another, battery to motor to kinetic energy. At each step there is some energy being “lost” as waste heat, like the Second Law predicts. This does not mean energy was destroyed. At each step we showed the waste energy being released. If we take that into account, the total energy is the same throughout! The system started with 1000 J of total energy. As you changed energy to other forms you “lost” a total of 200 J to the environment, but still had 800 J at the end… a total of 1000 J still! We are still obeying the First Law . 10/21/2005 © studyphysics.ca Page 1 of 7
Image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
In most of the stuff we study, we will assume that we are living in a “perfect” universe.
Image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern