Can an ideal spring ever experience an unbound state?

[marjine]

Homework Statement

Which of the following is a physical feature of a real spring which is NOT represented by the ideal spring potential energy graph?
A. a yield and breakage region
B. existence of bound states
C. existence of unbound states
D. region of compression where coils are touching
E. an equilibrium point of minimum energy

Relevant Equations

U = (1/2)ks^2 - E

This has never been covered in my lecture class before, and I can't find anything useful in my textbook. Considering I'm completely unfamiliar with this verbiage, I figured maybe if I google definitions of these terms I would be able to figure it out, but google doesn't have many definitions that apply to springs.

 

[kuruman]

Is this for a quantum mechanics class? The fact that bound and unbound states are mentioned makes me suspect that it is.

 

[marjine]

Is this for a quantum mechanics class? The fact that bound and unbound states are mentioned makes me suspect that it is.

No! I think those are might be distractor answers because this is physics I

 

[berkeman]

@marjine -- Can you say which of the other options you think may apply to a real vs. ideal spring?

I did find a couple things about springs and bound states, but let's leave those aside for the moment...

 

[marjine]

@marjine -- Can you say which of the other options you think may apply to a real vs. ideal spring?

I did find a couple things about springs and bound states, but let's leave those aside for the moment...

I think A and E are correct...

 

[kuruman]

I think A and E are correct...

What do you mean by correct? If you mean a feature that is "NOT represented by the ideal spring potential energy graph", then (E) is indeed a feature of the parabolic ideal spring potential energy. All parabolas with positive curvature have feature (E).

 

[marjine]

What do you mean by correct? If you mean a feature that is "NOT represented by the ideal spring potential energy graph", then (E) is indeed a feature of the parabolic ideal spring potential energy. All parabolas with positive curvature have feature (E).

Based on this, I ruled out all of the answer choices that contained E, and found that the correct answer is "A, C, D", but I still don't fully understand C.

 

[haruspex]

Based on this, I ruled out all of the answer choices that contained E, and found that the correct answer is "A, C, D", but I still don't fully understand C.

An unbound state is one in which the total mechanical energy could tear the system apart. That can't happen with an ideal spring.