A person with skin area 2 m2 and 0.97 radiation efficiency is at rest and has a skin temperature of 28 C in an environment with a uniform temperature of 22 C
.Calculate the heat loss rate in watts
To calculate the heat loss rate in watts, you can use the Stefan-Boltzmann Law, which states that the rate of heat loss (Q) is proportional to the product of the surface area (A) of the object, the radiation efficiency (ε) of the surface, and the temperature difference (ΔT) between the object and its surroundings.
The formula for calculating the heat loss rate is:
Q = A * ε * σ * ΔT
Where:
Q = Heat loss rate (in watts)
A = Surface area of the object (in square meters)
ε = Radiation efficiency (dimensionless)
σ = Stefan-Boltzmann constant (approximately 5.67 x 10^-8 watts/(meter^2 * Kelvin^4))
ΔT = Temperature difference between the object and its surroundings (in Kelvin)
Given values:
A = 2 m^2 (Surface area)
ε = 0.97 (Radiation efficiency)
ΔT = 28°C - 22°C = 6°C = 6 Kelvin (Temperature difference)
Plugging in the values to the formula:
Q = 2 * 0.97 * 5.67 x 10^-8 * 6
Calculating the result:
Q ≈ 6.821 x 10^-7 watts
Therefore, the heat loss rate is approximately 6.821 x 10^-7 watts.