PHYSICALITY VITALITY (Energy)
Again, students have heard the law of conservation of energy, but do they understand energy TRANSFER? Our demonstrations will focus on describing energy and its transfer. The first step to understanding energy conservation, however, is being able to understand types of energy. Some terminology we will use includes:
Energy: quantity related to the condition of an object (so energy helps to describe what an object is doing)
Non-Mechanical Energy: energy of motion on a subatomic level
Ex: chemical energy, thermal energy, heat, etc.
Mechanical Energy: energy of motion on a macroscopic level
Potential Energy:stored energy related to position
Kinetic Energy:energy related to being fast / slow
19. Pendulum to the Face |
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| To demonstrate that the total energy in a system is absolute, but energy can be converted to different forms, we will bring a bowling ball to one of our faces, release it, and then stand in place as we allow the bowling ball to swing back and forth returning to the face, but not hitting it, as the ball could not exceed the initial energy it was given. | |
20. Wilburforce Pendulum |
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 KE to PE energy conversions are typical, so to take this a step further, we will demonstrate a Wilburforce pendulum, in which there is a torsion oscillator (disk) attached to a spring oscillator. As elastic PE is released, the disk will gain KE. However, as the spring unwinds, the torsion oscillator will also rotate, giving it a different kind of KE. Eventually, the spring will stop bouncing, and the disk will simply rotate, then the disk will slow down, and the spring will begin bouncing again. The system is able to transfer these energies back and forth for quite some time, as there is little to transfer any energy away from the system. |
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21. Coupled Oscillators |
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| Two masses are hung on springs dangling from a piece of flexible metal. One mass is set into motion, and over the course of time, one can see the other mass begin moving, as the original one slows to a stop. These masses can transfer energy this way for quite some time. However, if one mass is placed into water, the effect is dramatically changed, as the water dampens the system. | |