Human Body Specific Heat

Reference data and engineering information about human body specific heat for thermodynamics applications.

humanbodyspecificheatData Table

Overview

Engineering reference data for Human Body Specific Heat in thermodynamics.

Key Formulas

First Law

$\Delta U = Q - W$

Energy is conserved — heat added minus work done.

Ideal Gas Law

$PV = nRT$

Relates pressure, volume, and temperature of an ideal gas.

Carnot Efficiency

$\eta = 1 - T_C/T_H$

Maximum efficiency between two temperatures.

Symbol	Description	Unit
$U$	Internal energy	J
$Q$	Heat	J
$W$	Work	J
$P$	Pressure	Pa
$V$	Volume	m³
$T$	Temperature	K

Specific Heats of Human Body and Comparative Substances
Substance	Specific Heat (cp)(J/(kg·°C))
Human Body (average) 1)	3470
Human Body (average) 2)	2980
Protein	1700
Wood	1700

The specific heat of the human body is highly dependent on its composition. The widely used average value of 3470 J/(kg·°C) is based on common assumptions, while the alternative average of 2980 J/(kg·°C) is a calculated value that reflects a range of 2444 to 3390 J/(kg·°C). This variation exists because different tissue types (muscle, fat, bone) have different specific heats. Up to 60% of the adult human body is water, which has a high specific heat of 4187 J/kg·°C and is the primary reason for the body's high overall heat capacity.

Unit Conversions

$1 \ \frac{\text{J}}{\text{kg·°C}} = 2.389 \times 10^{-4} \ \frac{\text{kcal}}{\text{kg·°C}} = 2.389 \times 10^{-4} \ \frac{\text{Btu}}{\text{lb}_m \cdot °F}$

References

Original Source

Source: engineeringtoolbox.com