Spring Deformation: Potential Energy Balance Incorrect?

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SUMMARY

The discussion centers on the energy balance in a spring deformation scenario, specifically addressing problem 13.68 from "Mechanics of Materials" by Beer and Johnston. Participants clarify that the spring accumulates potential energy when compressed and releases it when returning to its original length. Misunderstandings regarding the problem's requirements were resolved, emphasizing that the potential energy is not repeated but rather reflects the energy stored during compression.

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MomentumBJ
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Homework Statement
In this problem, a block that slides over an inclined plane reaches a spring at the bottom and compresses it.
Relevant Equations
In the energy balance T1 + V1 = T2 + V2, where:

T1 = (1/2)m*v1^2
V1g = m*g*h1
V1e = k*e1^2 = (1/2)*(30x10^3)( 0.050 )^2 = 37.5 J <--- compressed spring

T2 = (1/2)m*v2^2
V2g = mgh2
V2e = (1/2)*k*e2^2 =(1/2)*(30x10^3)(0.050 +x )^2 = 37.5 +1500*x + 15000*x^2

^----- again compressed


Thanks !
In the initial position the spring is previously compressed, then the block adds a force, and the spring is again deformed. I think the energy balance is incorrect; the potential energy of the spring is repeated.
 
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Welcome! :cool:

Could you provide a diagram for this problem?
The spring can only accumulate energy (as it gets compressed) and return it back into the system (as it returns to its original length).
 
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Thanks Lnewqban !, is the problem 13.68 form Beer and Jhonston. I misunderstood the question of the problem, the problem ask for additional compress, I got the complete deformation, there is not repeated term Thanks again.
 
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