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

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The discussion revolves around calculating power from the process of eating ice, using the formula P=W/t. The initial calculation yielded a power output of 0.56 watts, but a participant pointed out a discrepancy, suggesting the answer should be 560 J/s, indicating a factor of 1000 error. The confusion arose from the conversion of grams to kilograms, which was not properly addressed. It was later clarified that the latent heat value of 80 cal/g did not require conversion, resolving the error. The conversation emphasizes the importance of using consistent SI units in calculations.
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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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