Carnival glass is pressed glass, meaning that hot molten glass which may or may not contain colour of its own is poured into metal moulds and conforms to their shape. While the glass is still hot, various solutions of metallic salts are sprayed onto the surface and the piece is reheated. The result is a piece of iridescent glassware with …
Read More »What is carbon dating?
It is a method to determine the age of plants and fossils. Carbon has three naturally occurring isotopes, C12, C13 and C14. Of the three, C14 is radioactive in nature and has a half-life (decays to half the strength) of 5,730 years. Scientists measure the strength of C14 in the plant or fossil, and compare it with the expected strength …
Read More »What is captured rotation?
When a satellite, natural or artificial, is orbiting its parent planet (or primary) under some conditions, the satellite revolves around itself (or spins) quite fast relative to its period of rotation around the primary, and under some other conditions, both the periods coincide. The latter phenomenon leads to the satellite facing the primary always with the same side and it …
Read More »What is capnography?
The activity of measuring the concentration of carbon dioxide (CO 2 ) in respiratory gases during the respiratory cycle of a patient is called capnography. The equipment used in capnography usually plots the partial pressure of CO 2 in the exhaled breath as a wave form, with time on the x-axis and pressure of carbon dioxide on the y-axis. Infrared …
Read More »What is broken symmetry?
For spontaneous symmetry breaking to occur, there must be a system in which there are several equally likely outcomes. The system as a whole is therefore symmetric with respect to these outcomes (if we consider any two outcomes, the probability is the same). However, if the system is sampled (i.e. if the system is actually used or interacted with in …
Read More »What is Bowman’s Capsule?
Each human kidney contains about 1 million filtering units called nephrons. The nephron has a renal tubule and dilated blind end like a funnel. This dilated funnel like part is called Bowman’s Capsule. It has a tuft of capillaries. The fluid which comes out of these capillaries is filtered by Bowman’s Capsule. The renal tubules do further processing to make …
Read More »What is bow shock?
In aerodynamics, bow shock is a normal shock that occurs in front of an object within a supersonic flow. Unlike an oblique shock, the bow shock is not attached to the tip of the object in the flow. Oblique shock angles are limited in formation based on the corner angle and upstream Mach number. When these limitations are exceeded, a …
Read More »What is bluejacking?
Bluetooth is a radio wireless technology that allows computers, cell phones, laptops, etc. to exchange or talk to each other in a limited range. Bluejacking is the term based on two words — bluetooth and hijack. It refers to sending unnecessary and anonymous messages by using bluetooth enabled devices as a contact. In order to carry out bluejacking, both devices …
Read More »What is black gold?
Black gold is a term for oil or petroleum-black because of its appearance when it comes out of the ground, and gold because it made prospectors, drillers, and oil industry men rich. The oil industry in the United States began in 1859 when retired railroad conductor Edwin L. Drake (1819-1880) drilled a well near Titusville, Pennsylvania. His drill, powered by …
Read More »What is black energy?
In astronomy, black energy is a hypothetical form of energy that permeates all of space and tends to increase the rate of expansion of the universe. Black energy currently accounts for 73% of the total mass-energy of the universe. Black energy has been used as a crucial ingredient in a recent attempt to formulate a cyclic model for the universe. …
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