Power developed by a person on eating 100g of ice per minute is?

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SUMMARY

The discussion centers on calculating power developed by a person consuming 100g of ice per minute using the formula P=W/t. The work done (W) is calculated as W=Q=mL, where m is mass, L is latent heat, and Q is the heat energy. The correct calculation yields a power output of 0.56 watts, but a discrepancy arises when an answer of 560 J/s is provided, indicating a misunderstanding in unit conversion. The error is attributed to the latent heat value of 80 cal/g, which does not require conversion from grams to kilograms.

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Mimosapudica
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Homework Statement
Power generated is the work done per unit time. Also latent heat of ice is 80cal.
Relevant Equations
P=W/t
W= Energy = heat generated ?
Heat Q= mass x latent heat
P=W/t
W=Q= mL = (100x 80x 4.2)/1000 (kg x J/kg)
= 33.6
t= 1 minute= 60s
P= 33.6/60= 0.56 watt...
but the answer provided is 560J/s...?
 
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Looks like you are out by a factor of 1000. What's usually the reason for that?
 
PeroK said:
Looks like you are out by a factor of 1000. What's usually the reason for that?
I’m guessing the g to kg conversion has some problem, but shouldn’t we be converting it?
 
Mimosapudica said:
I’m guessing the g to kg conversion has some problem, but shouldn’t we be converting it?

Why don't you first write down all the quantities involved in SI units?
 
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PeroK said:
Looks like you are out by a factor of 1000. What's usually the reason for that?

Oops.. latent heat is 80 cal/g .. So it doesn’t need conversation.. that was a careless error.. thank you.
 
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