This article discussed applications of first order ordinary differential equations to real life systems, various types of differential equations with examples are presented. When a dead body is discovered somewhere, Police and detective security agency are eager to identify the time of death and what caused the death. In this article, Newton’s Law of cooling is used to estimate time of death of a dead body discovered in the midnight with the aid of information about the body’s surrounding temperature. It is discovered in this research that Newton’s law of cooling only works when temperature of the body’s surrounding is kept constant. The study also considered other applications of first order differential equations such as population growth model and radioactive decay of radioactive isotopes and illustrative example are given in each case
Keywords: applications of differential equations, population growth model, radioactive decay
