Energy Rules! Introduction

Units:

Energy Rules!

Section A. Introduction

This unit will look at how energy can be transferred and converted, and the natural limitations to the amount of energy that anyone or anything can use.

Energy Transfer
Energy can be transferred from one location to another, as in the sun's energy travels through space to Earth. The two ways that energy can be transferred are:

1. Doing work, such as pushing an object
Work (Man Pushing Wheelbarrow)

Radiator
2. Transferring heat through conduction, convection, and radiation

Energy Conversion and the Laws of Thermodynamics

Energy can neither be created nor destroyed, it can only be converted from one form to another. This is the first law of thermodynamics.

For example, the chemical energy in coal can be converted into thermal energy.

With each energy conversion from one form to another, some of the energy becomes unavailable for further use. This is the second law of thermodynamics.

For example, the thermal energy released by burning coal is eventually dispersed into the environment and cannot be used again. The measure of this dispersal of energy is called "entropy." The entropy of an unburned piece of coal and its surroundings is lower than the entropy of the ashes, cinders, and the warmed surroundings due to burning that piece of coal.

Next reading: To explore energy transfer and the laws of thermodynamics more in-depth, please proceed to Energy Rules! - Section B. Energy Transfer.

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