Insulated Pizza Delivery Bags - Essay Example

Once an isolated system is created, the first law guarantees that the energy (heat is a form of energy) will remain constant inside the system, which means whatever is in the bag will have a constant temperature, since the temperature is a measure of heat.Another way to phrase the first law of thermodynamics is: "energy can neither be created nor destroyed," given that the isolated system is one that does not allow energy nor matter to cross its boundary it is easy to see how an isolated system can keep its temperature constant.

The second law of thermodynamics: 'The entropy of any isolated system always increases in the course of any spontaneous change.'Another way to put it is that energy's ability to do work always decreases. In terms of heat, work is done by heat's transition, and so for the energy's ability to do work to decrease (i.e. for entropy to increase), the systems would reach their maximum entropy when they have the same temperature, which would mean that they will no longer be able to exchange heat between them and therefore would not be able to do work.

As isolated systems, the pizza bag's entropy increases, however, the pizza bag and the surroundings together have an entropy that does not increase, this does not violate the second law of thermodynamics since it states that only entropy of an isolated system can increase. The entropy of the isolated system (such as the pizza bag) and the surroundings together cannot both increase since this would require energy leaving the boundary of an isolated system which, by the definition of the isolated system, cannot happen.