Change in thermal energy

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Homework Statement



A block of mass M is pulled at constant speed with force F a distance d across a surface. Using the energy principle, what can you say about the change in thermal energy of the block?

a) [PLAIN]https://s3.lite.msu.edu/adm/jsMath/fonts/cmr10/alpha/144/char01.pngEtherm[PLAIN]https://s3.lite.msu.edu/adm/jsMath/fonts/cmmi10/alpha/144/char3C.png0 [Broken] [/B]
b) [PLAIN]https://s3.lite.msu.edu/adm/jsMath/fonts/cmr10/alpha/144/char01.pngEtherm=0 [Broken]
c) [PLAIN]https://s3.lite.msu.edu/adm/jsMath/fonts/cmr10/alpha/144/char01.pngEtherm[PLAIN]https://s3.lite.msu.edu/adm/jsMath/fonts/cmmi10/alpha/144/char3E.png0[/B] [Broken]


Homework Equations




The Attempt at a Solution



I believe the change in thermal energy is 0 (b) because it is being pulled at a constant speed so nothing is actually changing. Is my logic correct to say it is b?

I only have one attempt left
 
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Answers and Replies

  • #2
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Of it's traveling at constant speed, then what can you say about the presence or absence of a friction force?
 
  • #3
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Of it's traveling at constant speed, then what can you say about the presence or absence of a friction force?

If you are at constant speed, that means that the acceleration you are providing is equal to the deceleration from the friction. If those are not equal then the speed is increasing or decreasing. KE isn t changing. However, heat it formed so there would be a positive change of thermal energy? So C?
 
  • #4
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If you are at constant speed, that means that the acceleration you are providing is equal to the deceleration from the friction. If those are not equal then the speed is increasing or decreasing. KE isn t changing. However, heat it formed so there would be a positive change of thermal energy? So C?
If you are at constant speed, that means that the acceleration you are providing is equal to the deceleration from the friction. If those are not equal then the speed is increasing or decreasing. KE isn t changing. However, heat it formed so there would be a positive change of thermal energy? So C?
Correct.
 

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