Rubber Bands and Energy Dissipation

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SUMMARY

The discussion centers on the thermodynamics of rubber bands, specifically the conversion of mechanical energy into heat when a rubber band is stretched. Participants confirm that some energy is indeed converted to heat, but the exact percentage varies based on experimental conditions. The concept of an "ideal rubber band" is introduced, suggesting that heat loss can theoretically be minimized. However, real-world factors such as thermal conductivity and emissivity play significant roles in energy dissipation.

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  • Understanding of thermodynamics principles
  • Familiarity with energy conversion concepts
  • Knowledge of thermal conductivity and emissivity
  • Basic grasp of mechanical properties of materials
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  • Research the thermodynamics of rubber bands and energy dissipation
  • Explore the concept of ideal materials in thermodynamic processes
  • Study the effects of thermal conductivity on energy loss in materials
  • Investigate experimental methods to measure heat loss in rubber bands
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pallidin
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Greetings all...

When I pull a fairly good size/quality rubber band and then quickly hold it against my lips, I feel it to be quite hot.
I assume that some of the energy used in stretching the rubber band is converted into heat by virtue of the properties of a "rubber band"

My question is this: Is this energy "loss" appreciable? That is(speaking hypothetically), if I pull with 10 lbs of force, is 1 pound of force converted into heat? Or is this conversion a real but "negligible" factor(much less than 1-lb in my hypothetical scenario)

Thank you.
 
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http://www.fofweb.com/Onfiles/SEOF/Science_Experiments/5-39.pdf#search='thermodynamics%20of%20a%20rubber%20band'

"[URL

pp.12-14

Edit links --- OK, now the stinkin' linkin' is workin'.
 
Last edited by a moderator:
Thanks for your response, but links are not working for me. Maybe something on my end.
 
Google "thermodynamics of a rubber band" and look at items 1 and 14. They're both PDF files, and for who knows what reason that's a function of my versions of Windows and IE, my ISP's software, and PF software, PDF links won't parse, and "insert link" doesn't seem to have done the trick --- you got "cannot display page" I presume?
 
Bystander said:
Google "thermodynamics of a rubber band" and look at items 1 and 14. They're both PDF files, and for who knows what reason that's a function of my versions of Windows and IE, my ISP's software, and PF software, PDF links won't parse, and "insert link" doesn't seem to have done the trick --- you got "cannot display page" I presume?

Yes, I am getting a "cannot display page". I will take your advise and do the Google seach as you stated. Thanks.
 
"A related interesting property which makes a nice demonstration is to
stretch a rubber band with a weight and heat it with a hair dryer. The
length of the rubber band will decrease, unlike most materials which would
lengthen, I.e. expand, when heated."

From: http://www.Newton.dep.anl.gov/askasci/gen99/gen99976.htm
 
OK, I guess I'm asking this: With an event of "stretching" a rubber band, some amount of force is converted to radiated IR.
Is there a "percentile" qoutient? Is it 10%, 1%, .001%, etc...
Granted, it depends on the experiment. But surely there is some qualitative value with respect to this.
 
pallidin said:
OK, I guess I'm asking this: With an event of "stretching" a rubber band, some amount of force

Not "force," energy, the integral of force times displacement.

is converted to radiated IR.
Is there a "percentile" qoutient?

In principle, the heat loss from the rubber band can be restricted to zero; this is part of "the ideal rubber band." So, no.

Is it 10%, 1%, .001%, etc...
Granted, it depends on the experiment. But surely there is some qualitative value with respect to this.

Qualitative? Yes, the rubber band is going to lose heat to the environment at a rate determined by thermal conductivity of materials in contact with it, the emissivities of surroundings, and this all gets back to comparisons of idealized adiabatic processes with real processes --- you can approach ideality in this case with insulation and radiation shields. What you then observe is a rubber band, the temperature of which is a reproducible function of elongation.
 

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