Conservation of energy experiment

AI Thread Summary
In the conservation of energy experiment, a cart travels downhill on an air track, allowing for the calculation of kinetic and gravitational potential energy to demonstrate that total energy remains constant. The discussion focuses on whether the experiment can still show energy conservation if the mass of the cart is unknown. It is concluded that mass appears in both kinetic and potential energy equations, but it cancels out when calculating total energy. Therefore, the conservation of energy can be demonstrated without knowing the mass. This confirms that the principles of energy conservation hold true regardless of mass.
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Homework Statement


We had an air track and let a cart of mass m travel downhill. The we calculated the velocity and firther the kinetic energy K and the gravitational energy U. We did this to show that the total energy in the system stays constant.

Now I need to answer the question if I could still show that the total energy would be conserved if the mass was unknown.


Homework Equations


K=1/2mv^2
U=mgh



The Attempt at a Solution


I was looking at the parts where the mass would be involved. This seems to be in both formulas. Thus, my guess is that the mass would be cancel out and it would not matter if I know the mass or not. I could write initial kinetic energy + initial potential energy = final kinetic energy + final potential energy.
My problem is that I do not know if I am thinking in the right direction. So, if someone could help me and let me know if I am right or wrong with my thought, that would be great.
Thanks.
 
Physics news on Phys.org
Yes, you are correct. The mass m would cancel out. Hence, you would not need it to simulate conservation of energy.
 

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