Purchase Solution

# Definition of heat and temperature

Not what you're looking for?

Does your cup of coffee contain heat? Does it contain temperature? Explain.

##### Solution Summary

We explain in detail how heat and temperature are defined.

##### Solution Preview

Heat and temperature are not fundamental properties of physical objects. These quantities only have a meaning at the level of a statistical description of physical objects. It is analogous to considering the average weight of people in a group and then asking if the group contains this average. While you can calculate it from the properties of the system, it only exists at the group level as a statistical quantity.

To be able to describe the macroscopic world we can observe in a tractable way, requires one to be able to eliminate the detailed physics of microscopic world of atoms and molecules that the macroscopic objects consists of. While we may also be interested in atoms and molecules, physics would not be useful in practice if you could not describe the behavior of things like a cup of coffee without having to invoke all the details of 10^25 molecules. The problem we then face is that the laws of physics don't allow for decoupling of the macroscopic and microscopic degrees of freedom of a system.

Take e.g. a ball that can collide with other balls. We know that we can describe the physics here using conservation of momentum and conservation of energy. Suppose that we take into account that the ball is not a point mass and that it consists of a large number of molecules. Then as far as conservation of momentum is concerned, there is no problem, because the sum of the momenta of all the molecules equals the momentum of the center of mass of the ball. But the total energy of the molecules is not equal ...

##### Intro to the Physics Waves

Some short-answer questions involving the basic vocabulary of string, sound, and water waves.

##### Variables in Science Experiments

How well do you understand variables? Test your knowledge of independent (manipulated), dependent (responding), and controlled variables with this 10 question quiz.

##### Classical Mechanics

This quiz is designed to test and improve your knowledge on Classical Mechanics.

##### Introduction to Nanotechnology/Nanomaterials

This quiz is for any area of science. Test yourself to see what knowledge of nanotechnology you have. This content will also make you familiar with basic concepts of nanotechnology.