Energy levels for mass confined to 1D box

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Homework Help Overview

The discussion revolves around calculating energy levels for a nitrogen molecule confined in a one-dimensional box, specifically focusing on the lowest two energy levels and the characteristic temperature associated with them.

Discussion Character

  • Exploratory, Conceptual clarification, Problem interpretation

Approaches and Questions Raised

  • Participants discuss the calculations of energy levels using the provided formula and express uncertainty about the reasonableness of the characteristic temperature result. Questions arise regarding the understanding of the term "characteristic temperature."

Discussion Status

Some participants have provided insights into the implications of the calculated temperature, suggesting that the results may indicate the system's behavior at low temperatures. There is acknowledgment of the calculations being correct, but concerns remain about the interpretation of the results.

Contextual Notes

Participants note the challenge of assessing the reasonableness of results without prior experience with nanometer-scale systems, highlighting the potential for confusion regarding new terminology.

SalfordPhysics
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Homework Statement


For a nitrogen molecule, calculate the lowest 2 energy levels and the characteristic temperature;
Mass of molecule = 2.33x10-26[kg]
Length of box = 10-9[m]

Homework Equations


E = n2.h2/8mL2 (n=1,2,3,...)

Characteristic Temperature (Tc) -> when thermal energy kBT = energy spacing of lowest 2 levels.

The Attempt at a Solution


[/B]
E1 = h2/(8).(2.33x10-44)
= 2.358x10-24 [J]

E2 = n2.(E1) = 4(E1) = 9.432x10-42

Tc = (E2 - E1)/kB = 7.074x10-24 / kb = 0.512 [Kelvin]

The final answer quite simply does;t seem right to me, but I have checked numerous times my calculations. Can anyone clarify please.
 
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Why does it sound wrong?
 
Just doesn't seem like 0.5 Kelvins is a reasonable answer. Main problem is that the term characteristic temperature is a new one and not quite sure of its understanding.
 
Unless you have some common experience with nanometer size boxes, how can you even expect that you can tell what is a reasonable answer?
Your calculations seem OK. The result means that the system will be in the ground state only at very low temperatures. Otherwise will be very likely in excited states, due to the thermal excitation.
 
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Thanks nasu, this makes sense.
 

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