Chapter 14, Problem 61PE

Thermography is a technique for measuring radiant heat and detecting variations in surface temperatures that may be medically, environmentally, or militarily meaningful.(a) What is the percent increase in the rate of heat transfer by radiation from a given area at a temperature of $\text{34}.0°\text{C}$ compared with that at $\text{33}.0°\text{C}$, such as on a person’s skin? (b) What is the percent increase in the rate of heat transfer by radiation from a given area at a temperature of $\text{34}.0°\text{C}$ compared with that at $\text{2}0.0°\text{C}$, such as for warm and cool automobile hoods?

Figure 14.35 Artist’s rendition of a thermograph of a patient’s upper body, showing the distribution of heat represented by different colors.