Thermodynamics and Order

Trevor Craig

Energy Science 110

Thermodynamics and Order

9/11/11           

This lecture was about energy and how energy is what keeps our communities and lives together. Energy is everywhere, without energy life would not exist. Energy is what runs our cities, energy is what makes the plants grow, energy holds our buildings up, and energy is everywhere we look. So what is energy? Energy is the capacity to do work, and work= force * distance.  Force is mass * acceleration, and is measured in Newton’s, 1N= 1kg*(m/s^2). Energy is measured in joules.

            The amount of energy obtained from a substance varies. There is a reason we use gasoline in our cars instead of things like wood, wood burns at a 12-16 MJ/kg where gasoline burns at 42-44 MJ/kg. At the moment, most of our energy comes from gas and oil, but maybe someday it will come from other sources, like natural gasses, because methane burns at 50 MJ/kg which in comparison of gasoline has a much higher MJ/kg.

            Often times when we are talking about energy we have to mention power. Power is used to help us compare energy. Power is work/time or energy/time. For power the common unit name is watts, 1 watt=1 joule per second. I found it very interesting to look at the amount of watts different things used, for example 1 candle uses 5W, where a bowing747 uses 60 MW. Energy runs our communities and cities, so how much power does that take? Well for 1 human resting they are using 80W compared to the United States primary energy consumption being 3.1*10^ 12W, that is a lot of power.

            The United States uses a lot of energy but the energy is never truly lost, it just changes form. Energy can never be lost or gained. Energy takes many different forms some more useful than others. Here are just a few of the different energy forms: electromagnetic, chemical, thermal, kinetic, electrical, nuclear, and potential. So if energy can never be destroyed why can’t we just continue to use 1 tank of gas or make a perpetual motion machine? The reason we can’t create these sort of things is because all energy conversions are less than 100% effective, usually some energy degrades to heat

            Sometimes the energy of something is usable and other times it is not. The higher energies tend to have higher temperatures and more organization. Another way we measure these energy qualities is by the calorie, 4.18 J (N x m) = 1 calorie. Energy is what organizes our communities and lives, this complexity is not free; we must use energy in order to keep this organization and complexity. Without energy we would be unable to live, with it we are able to do amazing things.

Disintegrate-Break up into parts, typically as the result of impact or decay.

Coherent- Logical and consistent.

ENSC110 Craig Thermodynamics and Order