Heat Capacity Calculation Check.

[grahamreitz]

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
T_f = temperature final
T_i = temperature initial

Q = m * c * (T_f - T_i)

m = 5 g = 0.005 kg
c = 450 J/kgC (Nichrome)
T_f = 45 C
T_i = 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

 

[Q_Goest]

Looks good to me.