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Throughout my limited physics career (high school, first year university) I was introduced to concepts such as potential energy, kinetic energy, and work. Naturally, I was taught about potential energy using the whole gravity analogy. A brick at height h has more potential energy than a brick at height 0, provided h>0.
Now one thing really confused me.
1. Homework Statement
A pan of negligible mass is attached to two identical springs of stiffness k = 250 N/m. If a 10kg box is dropped from a height of 0.5m above the pan, determine the maximum vertical displacement d. Initially each spring has a tension of 50 N.
The springs are each 1 m long.
F=-kx
W = integral of F with respect to dx
potential energy + work + kinetic energy = potential energy + kinetic energy
The question is solved by a solution manual online by considering taking the potential energy of the spring, the box, and the earth. The thing is, I originally never learned that we could do this. I learned that we can only take the potential with respect to one object.
Naturally, this confused me. Exactly what are the limits to taking both of these objects as one system? How would we handle kinetic energy (if both the spring and the mass were moving with their own independent velocities)
Here is how it is solved:
Now one thing really confused me.
1. Homework Statement
A pan of negligible mass is attached to two identical springs of stiffness k = 250 N/m. If a 10kg box is dropped from a height of 0.5m above the pan, determine the maximum vertical displacement d. Initially each spring has a tension of 50 N.
The springs are each 1 m long.
Homework Equations
F=-kx
W = integral of F with respect to dx
potential energy + work + kinetic energy = potential energy + kinetic energy
The Attempt at a Solution
The question is solved by a solution manual online by considering taking the potential energy of the spring, the box, and the earth. The thing is, I originally never learned that we could do this. I learned that we can only take the potential with respect to one object.
Naturally, this confused me. Exactly what are the limits to taking both of these objects as one system? How would we handle kinetic energy (if both the spring and the mass were moving with their own independent velocities)
Here is how it is solved: