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Rate of vaporisation

  • Thread starter roam
  • Start date
  • #1
1,266
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Homework Statement



During exercise the body loses 240 W of heat due to the evaporation of sweat. Assuming that the latent heat of at body temprature is 2255 kJ/kg, determine the rate of vaporisation of sweat.

answer = 106 mg/s

Homework Equations



L=Q/m

The Attempt at a Solution



What formula do I need to use here? The only formula I can think of is the one with latent heat and heat energy Q=mL. But this formula only gives mass and doesn't give the rate of vaporisation!
 

Answers and Replies

  • #2
ideasrule
Homework Helper
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If 240J is added to the sweat per second and it takes 2255 000 J to vaporize one kg of sweat, how much is vaporized per second? You don't need any formulas, just logic.
 
  • #3
1,266
11
If 240J is added to the sweat per second and it takes 2255 000 J to vaporize one kg of sweat, how much is vaporized per second? You don't need any formulas, just logic.
I'm not quite sure if I understand correctly, do you mean sweat+240J/2255000? :confused:
 
  • #4
1,266
11
And it is 240 W not Joules...
 
  • #5
1,929
228
And it is 240 W not Joules...
a Watt is just a Joule per second.
 

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