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What is the center of buoyancy?

For a vessel of uniform construction, such as a wood block, the center of gravity is at the geometric center. When the block floats in water, the center of buoyancy is at the geometric center of the part of the block that is under water. Since ships are not of uniform construction, their designs and the distribution of their loads affect both their centers of gravity and the centers of buoyancy.

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What is the Wobble hypothesis?

Each tRNA contains a three-base anti-codon that is complementary to a codon in transcribed mRNA. The first two pairs need to be complementary for binding to occur, but the third pair does not always need to be complementary. This is the wobble, or allowance of degeneracy, in the genetic code.\nSince mRNA is made up of four different nucleotide bases (A, G, U, and C) and codons are made up of three of these bases, 64 possible codon configurations exist. Additionally, it would be expected that there would be 64 tRNA and 64 associated amino acids. However, only 21 amino acids exist, which means t..

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What is the difference between a tsunami and a tidal wave?

The moon's gravitational pull causes the ocean to bulge on the side facing it. Inertia causes the ocean to also bulge on the opposite side facing the moon. The process of the ocean bulging as a result of these forces creates lunar tides. Most locations on Earth experience two high tides and two low tides every 24 hours.\nA tsunami is a series of waves that sends surges of water onto land. Tsunamis are most often caused by large undersea earthquakes that occur at tectonic plate boundaries. When the ocean floor rises or drops suddenly due to an earthquake, it displaces the water above it, c..

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What are different types of crystalline structures?

The shapes of crystals are distinct but difficult to imagine until seen. Also, names can be misleading. For example, a cubic crystal is not always cube shaped. Within the isometric classification alone, there may be cube shapes, octahedrons (eight faces) and dodecahedrons (10 faces). Most classes and shapes are symmetrical, but the triclinic class is usually asymmetrical, making for some strange crystal shapes.\nChemical properties that are used to group crystals include covalent, metallic, ionic and molecular. There are distinct differences in each of these. For instance, a covalent crystal h..

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What type of volcano is Mauna Kea?

Mauna Kea's status as a post-shield volcano is evidenced by its low eruption rates, its lack of a caldera at the summit, the long fissure vents radiating from its summit, its steep and irregular topography and the chemical composition of its lava. These traits are in contrast to neighboring volcanoes Mauna Loa and Kilauea, both of which are still active. Shield volcanoes are so-named because their mountains take the shape of shields due to lava outflow.

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Why does iodine turn starch blue?

Amylose molecules are made up of single strands of glucose molecules shaped like springs. When iodine is added to a starch, it adheres to the beta amylose molecules because of their solubility. The starch pushes the iodine into a line in the middle of the amylose coils and creates a transfer of charge between the iodine and starch. This causes a change in the arrangement of electrons and energy level spacings. The new spacings absorb visible light differently and create the deep blue color.\nIodine is often used to test foods for starch. Adding iodine to potatoes, dried beans, rice, bread and ..

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What is the concept of natural selection?

The existence of variations within a species begins the process of natural selection. The variation may be in either appearance or behavior. The ability of a variation to be inherited by offspring is central to the concept of natural selection. In order to impact future generations over time, the variation must be able to be passed on or it is not a factor in determining future traits of the species.\nThe varying trait must give the organism an advantage in the quest for resources in its environment in order for natural selection to be in its favor. Advantageous traits are often retained in th..

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What colors make purple?

Purple is most notable for its use in royalty. As such, it represents the notion of affluence and wealth. It can also be used to represent imagination and creativity. Purple is the most powerful wavelength on the visible light spectrum, being only one step away from the power of x-rays. Lighter shades of purple can represent light-hearted notions, such as romance, while darker shades tend more towards the representations of intelligence. Purple can also represent several negative traits, such as conceit and pomposity.

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What is a gradient in Earth science?

In order to find the gradient in a topographical setting, one must know two things: the elevation of two points and the distance between the two points. Once these values are known, the gradient can be found by dividing the change in field value, or the change in elevation, by the distance. The higher the gradient value is, the steeper the slope is.

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What effect does plastic have on the environment?

Chemist Katsuhiko Saido of Nihon University in Japan led a team of researchers to discover that plastic breaks down quickly in the ocean, releasing chemicals such as bisphenol A, or BPA, and styrene trimer. Styrene trimer is potentially carcinogenic, while BPA interferes with animal endocrine systems, disrupting reproductive function. This same breakdown may also occur in landfills where chemicals potentially leech into groundwater supplies. According to the Centers for Disease Control and Prevention, 93 percent of people exhibit discernible levels of bisphenol A in urine. In the world's ..

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