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When was solar energy discovered?

Solar energy improved in 1953 when Calvin Fuller, Gerald Pearson and Daryl Chapin discovered the silicon solar cell. This was the first practical application of solar energy, as the cell created enough electricity to run small electrical devices.\nBy 1956, solar cells became available commercially. The price of $300 per 1 watt cell, however, was far more than the average consumer could afford. In the early 1970s, Exxon discovered a way to lower the cost of solar cells to $20 per watt, making them more affordable for consumers.

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What is the hypochlorite ion?

The hypochlorite ion forms different salts with metals. Typical examples are sodium hypochlorite, NaOCl, and calcium hypochlorite, Ca(OCl)2. Hypochlorite salts are used as bleaches, disinfectants and for water treatment due to their oxidizing and chlorinating effects. The hypochlorite ion is unstable and decomposes into a mixture of chloride ions, Cl-, chlorate ions, O3Cl- and molecular oxygen, O2.

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What is the difference between a BJT and a FET?

A BJT relies on two different charge carriers, hole and electron for its conduction level. An FET relies on one charge carrier, either hole or electron for its conduction level. An n-channel FET has electron as its charge carrier. Hole is the charge carrier for a p-channel FET. BJTs can be npn or pnp transistors.Other differences between a BJT and an FET are in terms of temperature stability and size. Normally, an FET is smaller with a more stable temperature than a BJT.

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How do you convert meters per second to miles per hour?

For the sake of simplicity, the following example converts time instead of distance. Meters per second must first be in fraction form, so that meters is the numerator and seconds is the denominator. Now, this fraction must be multiplied by 60 seconds per one minute. The last conversion for time is multiplying this new value by 60 minutes per one hour. Now, the units are meters per hour.\nTo convert distance, use the new value of meters per hour and multiply that by one mile per 1609.34 meters. Through dimensional analysis, the units of meters per second are now miles per hour.

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At which stage of cellular respiration is the most ATP produced?

Three of the four stages of cellular respiration produce ATP. The first stage, glycolysis, occurs in the cytoplasm of the cell. During this stage, one glucose molecule is broken into two pyruvic acid molecules. This results in the production of two ATP molecules for every glucose used.\n\nThe pyruvic acid is taken to the mitochondria during the transition reaction, which is the second stage of cellular respiration. The pyruvic acid is then converted to acetyl CoA. During the Krebs cycle, which occurs in the mitochondrial matrix, all the hydrogen atoms are taken from the acetyl CoA. Four ATP mo..

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What are some examples of a bottleneck effect?

When any given population's size quickly becomes very small, this is referred to as a bottleneck effect. Because the size is reduced so quickly, the genetic variation decreases as well. The Toba catastrophe is an example of a human bottleneck effect that occurred about 70,000 years ago. This was a supervolcanic eruption that resulted in a global volcanic winter that lasted anywhere from 6 to 10 years, and a cooling episode that possibly lasted for 1,000 years after that.One type of bottleneck effect is called a founder effect. The founder effect is an instant event, and occurs when a smal..

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What is MVA power?

Megavolt amperes are calculated using other derivatives, such as kilovolt amperes. One thousand kilowatt amperes are equal to one megawatt ampere. When installing power generators and transformers in an electric power substation, engineers always consider the substation’s capacity; thus, they install generators and transformers with similar MVA power capacities. Additionally, MVA power is used as a basis for estimating the amount of electrical power that an industry or residential area requires, which should match the MVA power capacity at the substation. Different power transformers come wi..

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Is sodium chloride a pure substance?

In a pure substance, the chemical and physical properties are always the same in any given sample. For instance, table salt is always made of one molecule of sodium bonded to one molecule of chlorine. Other examples of pure substances include water, sodium bicarbonate and sucrose, also known as pure table sugar. Water is a pure substance because the chemical composition always consists of two hydrogen atoms bonded to one oxygen atom.

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How long does it take for a tree to grow?

When it comes to peach trees, the length of time it will take for them to bear fruit depends on the conditions in which they are grown. They can grow to be at least 20 feet tall. \nRedwood trees may take only a few years to begin growing cones, or it can take decades for this to occur. They will reach a height of about 30 feet in 10 years and between 100 to 130 feet after 50 years. Although it takes many decades for the redwood to grow to its full height, it is quite the impressive tree to see.

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What is the function of RNA polymerase?

To begin transcription, RNA polymerase II binds to a segment on a gene called a promoter, explains North Dakota State University. The promoter consists of nucleotide sequences, which are TATAAT and TTGACA in eukaryotes and TATA and CAAT in prokaryotes. T stands for a thymine nucleotide, A for adenine, G for guanine and C for cytosine, notes Pearson Prentice Hall. In bacterial cells, a molecule called a sigma factor must be present for RNA polymerase II to be able to identify the promoter. In eukaryotic cells, transcription factors help RNA polymerase II locate the promoter, explains North Dako..

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