Answer:
Mohs hardness, rough measure of the resistance of a smooth surface to scratching or abrasion, expressed in terms of a scale devised (1812) by the German mineralogist Friedrich Mohs. The Mohs hardness of a mineral is determined by observing whether its surface is scratched by a substance of known or defined hardness.
Related Topics: hardness
To give numerical values to this physical property, minerals are ranked along the Mohs scale, which is composed of 10 minerals that have been given arbitrary hardness values. The minerals contained in the scale are shown in the Table; also shown are other materials that approximate the hardness of some of the minerals. As is indicated by the ranking in the scale, if a mineral is scratched by orthoclase but not by apatite, its Mohs hardness is between 5 and 6. In the determination procedure it is necessary to be certain that a scratch is actually made and not just a “chalk” mark that will rub off. If the species being tested is fine-grained, friable, or pulverulent, the test may only loosen grains without testing individual mineral surfaces; thus, certain textures or aggregate forms may hinder or prevent a true hardness determination. For this reason the Mohs test, while greatly facilitating the identification of minerals in the field, is not suitable for accurately gauging the hardness of industrial materials such as steel or ceramics. (For these materials a more precise measure is to be found in the Vickers hardness or Knoop hardness) Another disadvantage of the Mohs scale is that it is not linear; that is, each increment of one in the scale does not indicate a proportional increase in hardness. For instance, the progression from calcite to fluorite (from 3 to 4 on the Mohs scale) reflects an increase in hardness of approximately 25 percent; the progression from corundum to diamond, on the other hand (9 to 10 on the Mohs scale), reflects a hardness increase of more than 300 percent.
Answer:
Explanation:
The Byzantine Empire influenced many cultures, primarily due to its role in shaping Christian Orthodoxy. The modern-day Eastern Orthodox Church is the second largest Christian church in the world. Orthodoxy is central to the history and societies of Greece, Bulgaria, Russia, Serbia, and other countries.
Byzantine architecture, particularly in religious buildings, can be found in diverse regions from Egypt to Russia. During the Byzantine Renaissance—from 867 to 1056—art and literature flourished. Artists adopted a naturalistic style and complex techniques from ancient Greek and Roman art and mixed them with Christian themes. Byzantine art from this period had a strong influence on the later painters of the Italian Renaissance.
In the period following the sacking of Constantinople in 1204 and the fall of Constantinople in 1453, people migrated out of Constantinople. Among these emigrants were many Byzantine scholars and artists, including grammarians, poets, writers, musicians, astronomers, architects, artists, scribes, philosophers, scientists, politicians and theologians.
The exodus of these people from Constantinople contributed to the revival of Greek and Roman studies, which led to the development of the Renaissance in humanism and science. Byzantine emigrants also brought to western Europe the better preserved and accumulated knowledge of their own Greek civilization.
Answer:
He is a natural born citizen.
Explanation:
Answer:
Chairman Mao has at least five major contributions to the Chinese nation, to the New China, and to the Chinese Communist Party. First, he led the Chinese people through a long-term revolutionary struggle and finally achieved national independence and the liberation of the people and created a new China.
Explanation:
Chairman Mao has at least five major contributions to the Chinese nation, to the New China, and to the Chinese Communist Party. First, he led the Chinese people through a long-term revolutionary struggle and finally achieved national independence and the liberation of the people and created a new China.
The British had an empire to run. The way that they kept their economy healthy was through a system called mercantilism. ... The British even put taxes called duties on imported goods to discourage this practice. This pushed the colonists to buy only British goods, instead of goods from other European countries.
