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What are the different forms of energy?

Kinetic energy refers to an object or system in motion. For example, a ball flying through the air possesses kinetic energy. Potential energy is an object's potential to turn into kinetic energy. A book sitting on a table has potential energy because it could fall off the table. Thermal energy is related to the temperature of a system. The higher temperature results in an increase in potential and kinetic energy.\nChemical energy is a form of microscopic potential energy. For example, glucose reacting with oxygen releases energy. Electrical energy produces electric currents that can be tr..

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What are some of the main properties of elastic fibers?

Elastic fibers are found in the lungs, veins, arteries, periodontal ligaments, skin, fetal tissue and other body structures. They are comprised of bundles of proteins and are produced by smooth muscle cells and fibroblasts in arteries. Elastic fibers are also referred to as yellow fiber, and elastic tissue is categorized as connective tissue proper.

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What is the "reptilian brain?"

The comparison of this section of the brain with that of reptiles emerged in the 1960s as the triune model of brain development. This model attempts to describe the evolution of the mammal brain as a series of advances that took place without erasing the brain's evolutionary history. Under this model, the modern mammalian brain is essentially a reptile brain that has had two other sections, the limbic system and the neocortex, added to it over the 250 million years since mammals emerged as a distinct lineage.\nThe R-complex regulates many functions that mammals and reptiles have in common..

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What damage does a cyclone cause?

Cyclones are large areas of very low pressure. They're often called hurricanes when they occur in the Atlantic Ocean and typhoons when they occur in the Pacific Ocean. When viewed from above, cyclones produce spiral bands of arms that radiate from a central vortex. Meteorologists name cyclones to avoid confusion when more than one low-pressure system exists in a single ocean basin. The names associated with particularly destructive or deadly cyclones are often retired when the storm dies.\nTo qualify as hurricane-force, winds must maintain speeds of 74 miles per hour or higher. Such speed..

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What is the conversion factor from Celsius to Fahrenheit?

To convert from Fahrenheit to Celsius, simply reverse the formula. Subtract 32 from the value for degrees Fahrenheit, then multiply the quantity by 5 and divide it by 9. Both scales have been around since the 1700s. The Celsius scale is also sometimes referred to as the centrigrade scale, because it divides the interval between the freezing and boiling points of water into 100 units.

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What is the Friedmann universe theory?

General relativity suggests that space is not solid. It can bend into many different shapes and is, in fact, not expanding. It is the space between points in the universe that is expanding. The distances between these points become greater over time.\nThe space between clusters of galaxies can expand as well. However, the gravity within clusters of galaxies prevents the galaxies from expanding.\nIn 1931, six years after Friedmann's death from typhoid fever, Belgian physicist Georges Lemaitre proposed the idea known as the big bang theory with the aid of Friedmann's works. This theory..

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What are characteristics of terrestrial planets?

Although the four terrestrial planets have a solid surface, the individual planets have variant characteristics. Earth is the only planet with water on its surface, according to New Jersey University's Department of Astronomy.\nAll four planets have similar inner structures. Each has a crust, mantle and core under the surface, according to the University of Colorado at Boulder. Tectonic plates move within the structure of the planets. All of the terrestrial planets are inner planets, according to StarDate Online. Each terrestrial planet also shares a common formation through the clumping ..

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What is the definition of "electron sharing"?

Atoms are most stable when their outermost electron shell is complete. In order to complete the outermost shell, some atoms lose electrons to form positive ions while others gain electrons to form negative ions. However, some atoms share electrons with neighboring atoms to stabilize their outermost electron shell without forming ions. In such cases, neither of the atoms is ionized since the shared pair of electrons are not pulled a sufficient distance away from the nucleus of the atom to be considered "removed" from the atom. This imposes a distance constraint between the two atoms sharing the..

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What is sliding friction?

In engineering, sliding friction occurs in numerous types of sliding components, such as journal bearings, cams, linkages and pistons in cylinders. Static friction is the friction required to move two surfaces that are not in relative motion.\nThe sliding coefficient of friction is normally much lower than the static coefficient of friction. This difference can be experienced when braking a car in slippery conditions. If the wheels lock up, the primary friction between the tires and the ground changes from static friction to sliding friction because the tires are no longer rolling with the gro..

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What releases oxygen in photosynthesis?

From the perspective of the chloroplast, oxygen is waste. The carbon from carbon dioxide and the hydrogen from water are electrochemically combined into carbohydrates, and much of the oxygen is of no further use to the organism. When oxygenic photosynthesis first evolved 2 billion years ago, the result was a global catastrophe, as the new pollutant, diatomic oxygen, caused mass extinctions.\nAs semi-independent components of cells, chloroplasts are remarkably similar in both form and function. This has led to a widely supported theory that they stem from a common ancestor that incorporated its..

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