Matter as a form of energy

Just over 100 years ago, Albert Einstein developed his theory of special relativity. The theory was based on the idea that the laws of physics applied in the same way to all reference frames moving at constant velocities RELATIVE to one another. Since the speed of light (and all other electromagnetic radiation) in a vacuum is determined by the the physical laws of electromagnetics, then it is constant in every frame of reference, no matter how fast that frame is traveling with respect to the source of the light. In other words, the speed with which a light ray from a light bulb passes you is 300,000,000 meters per second regardless of whether you are running towards the light bulb or away from it, or standing still. This somewhat bizarre fact is just the tip of the iceberg.

Einstein discovered another result of the equivalence of reference frames traveling at constant relative velocities. The mass of an object depends on the frame from which it is viewed. Thus, its mass depends on its velocity or, more to the point, its kinetic energy effects it mass. With some brilliant insight he developed the fact that mass is transformable to energy at the rate that change in energy ( potential or kinetic or both ) is equal to change in mass times the square of the speed of light. Since the symbol "c" is used to mean the speed of light, this fact can be written as the energy content, E , of matter with mass, M, is given by :

E=Mc^2

We will discuss this a bit more as we explore energy in honors. AP classes will have to wait until April or May to get more on this subject in class.