March 22-25

If I could go back in time, I would tell myself about constant energy and energy conservation. I would remind myself over and over again that constant energy is when it stays the same, and that conservative is when there is some work done and the total energy isn't equal before and after. I would also tell myself about how what you include in your system affects the energy transfer. For example, if the earth is part of the system, there can be gravitational potential energy, btu without it in your system, you would say that the earth does work. Also, if there was friction, you could include the surface as part of the system and show the energy as constant with kinetic energy that turns into internal energy. Or, you could not include the surface and say that it did negative work.

There weren't any experiments that helped, but I liked the kinds of problems where we were given a situation and we had to say what the systems were and make bar graphs. The problem with the skier helped when we were given the scenarion, and then we had to make a bar chart for when only the skier is part of the system and when the earth and skier were part of the system. With the earth, we would say that the gravitational potential energy turned into kinetic energy, but without the earth, we would say that the earth does work on the system to give the skier knietice energy. It helped me understand about how the transfer of energey is different when you include or don't include certain objects in the system.