Entropy, unlike energy or momentum, is not a local property. It is a macroscopic quantity, valid for a collection of molecules. Although you can take such a collection and calculate the entropy per molecule, that has no meaning by itself. …
An amalgam is an alloy of mercury with one or more other metals. It is similar to considering steel to be an alloy of iron with other metals. Most metals will form an amalgam with mercury, with the main exceptions …
Human impact on the nitrogen cycle is diverse. Agricultural and industrial nitrogen (N) inputs to the environment currently exceed inputs from natural N fixation. As a consequence of anthropogenic inputs, the global nitrogen cycle has been significantly altered over the …
Light is affected by gravity, but not in its speed. General Relativity (our best guess as to how the Universe works) gives two effects of gravity on light. It can bend light (which includes effects such as gravitational lensing), and it can …
The effects of radiation depend on the type, energy, and location of the radiation source, and the length of exposure. The average person exposed to background radiation, including cosmic rays from the sun and radon from uranium in the ground; …
HIV infects a type of white blood cell in the body’s immune system called a T-helper cell (also called a CD4 cell). These vital cells keep us healthy by fighting off infections and diseases. HIV cannot grow or reproduce on …
Let us consider a neutral sphere made with metal. Since metal is a good conductor of electricity, so we have chosen the object made from metal. The neutral sphere is placed on an insulator sheet, as shown in the diagram …
One way to do this is to report the result of a calculation with the correct number of significant figures, which is determined by the following three rules for rounding numbers: When adding or subtracting numbers, round the result to the same …
Ammonia is the waste produced by the metabolism of nitrogen-containing compounds like proteins and nucleic acids. While aquatic animals can easily excrete ammonia into their watery surroundings, terrestrial animals have evolved special mechanisms to eliminate the toxic ammonia from their …
Cyclotron works on the principle that a charged particle is moving normal to a magnetic field experiences magnetic Lorentz force due to which the particle moves in a circular path. It consists of a hollow metal cylinder divided into two …