Heat Capacity Calculation Check.

AI Thread Summary
The heat capacity calculation presented involves determining the energy required to raise the temperature of a 5 g mass of Nichrome from 15°C to 45°C. Using the formula Q = m * c * (Tf - Ti), the calculated energy required is 67.5 J. With a power output of 14 W, the time to heat the material is computed to be approximately 4.82 seconds. The calculation appears to be correct, although the user notes that their temperature probe may be slow in response. Overall, the method and results of the calculation are validated.
grahamreitz
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Hello PF,

Is the following calculation correct for the amount of time it would take to raise the temperature of a given mass of material?

Q = heat in J
W = watts
m = mass in kg
c = specific heat in J/kgC
Tf = temperature final
Ti = temperature initial

Q = m * c * (Tf - Ti)

m = 5 g = 0.005 kg
c = 450 J/kgC (Nichrome)
Tf = 45 C
Ti = 15 C

Q = (0.005) * (450) * (45 - 15) = 67.5 J

W = 14

Time to heat material from 15 C to 45 C at 14 W:

t = J / W = (67.5 J)/(14 W) = 4.82 s

I'm not measuring this empirically. Although, my temperature probe is a little slow.

Thanks,
Graham
 
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