Such vibrating particles possess energy, both kinetic and potential (the latter due to the potential energy from the restoring Van der Waals forces), and this energy is within the objects themselves, so it is internal. These vibrations are not in-sync – they are quite random, and the vibrations spread to their neighbor molecules as well. When two surfaces slide across each other with kinetic friction, the surface molecules push and pull against each other, and as they are bound to their respective objects, they react by vibrating. In most macroscopic model calculations, the internal energy change that occurs in the system comes in the form of random motions of molecules in the participating objects. There is one subset of the internal energy category that deserves special mention. There is still much more we can do with this simple two-book model, and we will return to it in a future chapter. The quantity \(\Delta x_A-\Delta x_B\) is the distance that book \(A\) slides across book \(B\), and it is a positive number, which means that there is an increase in the internal energies of the two books. This makes sense, as it means that the amount of energy that goes into the internal energies of the books is a measure of the number of interactions between molecules at the surfaces of the books, and the distance that they slide across each other is directly related to the number of molecular interactions. While the work done by a Non-conservative force is irreversible in nature.=-\left(\Delta KE_B + \Delta KE_A\right)=-f\Delta x_B+f\Delta x_A=f\left(\Delta x_A-\Delta x_B\right)\] The work done by a conservative force is reversible in nature.Gravitational force is the most common conservative force present in the nature which is also the weakest one. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |