Final answer:
The negative sign in the Newton's law of cooling formula denotes the direction of heat flow from higher temperatures to lower ones. This supports the second law of thermodynamics, indicating reduction if an object's temperature is higher, and increase if less, than the surrounding temperature.
Step-by-step explanation:
In the formula of Newton's law of cooling, the negative sign is of great significance. This law is stated as: dT/dt = -k(T - Ts), where dT/dt is the rate of change of the object's temperature, T is the temperature of the object, Ts is the surrounding temperature, and k is a positive constant characteristic of the object and its environment.
The negative sign in the equation indicates that if the object's temperature (T) is higher than the surrounding temperature (Ts), the temperature of the object will decrease, hence the negative rate of change. Conversely, if the object's temperature is lower than the surrounding temperature, the object's temperature will increase, leading to a positive rate of change. Therefore, the negative sign in the equation reflects the direction of heat flow from high temperature to low temperature following the second law of thermodynamics.
Learn more about Newton's law of cooling