Students will show that energy is indeed conserved throughout the universe. Or find that it's not and probably win a nobel prize. Students will do this by setting up a system where energy fluctuates between potential and kinetic energy and see if energy is conserved throughout.
The Lab:
Students will attach a mass to a spring that hangs vertically. The mass will then be pulled down by gravity while the elasticity of the spring will pull the mass back up. The energy of the system will then be fluctuating between the gravitational potential energy of the mass/spring, the kinetic energy of the mass/spring, and the elastic energy of the spring.
The students will record of all these changes with a motion sensor and some clever physics calculations. They will add up all the energies to see if the total energy stays constant which theoretically it should barring alien interference.
Here is a picture of the student's heartfelt effort:
Here are the student's calculations:
Elastic PE in spring: 1/2 K (stretch)^2
KE of mass : 1/2mv^2
PE of mass: mg * y
PE of spring: m(spring) / 2 * g * y + mgh/2 *h = height of top of spring and y = bottom of spring
KE of spring 1/2 m(spring)/3 * V^2(mass)
GPE: 1/2 m(spring) * g * y (y = bottom of mass height)
The students then used logger pro to graph all of the energy over time. Then the students added all the energies to find the total energy and graphed that. After some clever menagering of the data with the professor's help the students were able to produce a total energy graph that was almost a straight line:
Hint: it's the light green one at the top
Conclusion:
Yay! The experiment was a success! Energy is conserved! All physics is saved!
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