In the investigation of a homicide or accidental death it may be quite important to estimate the time of death. From experimental observations it is known that the surface temperature of an object changes at a rate proportionalto the difference in temperature of the object and that of the surrounding environment or ambient temperature. This relationship is known as Newton's law of cooling. Thus, if T$($t$)$ is the temperature of the object at time t and Ta is the constant ambient temperature then:

dT$/$dt $=-$K$($T$-$Ta$)$