There are many different kinds of harps. The two main kinds are folk harps and pedal harps.
The folk harp is the older kind of harp, the oldest dating back to 3000 BC in Ancient Egypt. In these harps, each string can only make one note at a time. They are usually tuned so that playing each string in order sounds like playing all the white notes on a piano in order. This is called a diatonic scale. In some places, they are tuned so that playing each string in order sounds like playing all the black notes on a piano in order. This is called a pentatonic scale.
Folk harps can be found in many different sizes. The smallest ones can be less than half a meter tall and can have as little as 20 strings. The biggest ones can be almost 1.5 meters tall, have up to 40 strings, and can stand on the ground by themselves. These harps are too big to be lifted by one person.
The pedal harp was invented during the 1800s by a man in France. This is the kind of harp that is heard in most classical music and is used in the modern symphony orchestra, and for this reason it is often called a concert harp. Pedal harps are about two meters tall and have about 50 strings. The lowest and highest notes on a pedal harp are the same as the lowest and highest notes on a piano. They are very heavy, and need more than one person to move them. The frame is usually made out of metal.
Like the folk harp, the pedal harp is tuned like the white keys on a piano. However, it has seven pedals to let the harp player play music in different keys. Each pedal, named after the different musical notes, has three places. For the "A" pedal, the usual place makes all the "A" strings sound like a normal "A" ("A"-natural). The lower place makes all the "A" strings on the harp sound like "A"-flat, while the higher place makes all the "A" strings sound like "A"-sharp.
A cross-strung harp is a pedal harp that is chromatic and consists of two rows of strings. They cross near to the middle of the string without touching. The strings are in the order of the piano keys (7 plus 5) or in the order of the 6-plus-6 system.
Some instruments have the word harp in their name, but they are not really harps. The harp is such an old musical instrument, that people sometimes say "harp" when they mean any kind of instrument.
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Kassam Stadium
Kassam Staudium is an arena in Oxford, England. It is where Oxford United F.C. plays. It is the biggest arena in the blue square premier league conference national
Nucleotide
A nucleotide is an organic molecule. Nucleotides are the building blocks of the nucleic acids RNA and DNA. These two types of nucleic acid are essential biomolecules in all forms of life on Earth.
A nucleotide is composed of a nucleobase (nitrogenous base), a five-carbon sugar (either ribose or 2-deoxyribose), and one phosphate group. Nucleotides contain either a purine or a pyrimidine base. Ribonucleotides are nucleotides in which the sugar is ribose. Deoxyribonucleotides are nucleotides in which the sugar is deoxyribose.
In DNA, the purine bases are adenine and guanine, and the pyrimidines are thymine and cytosine. RNA uses uracil in place of thymine. Adenine always pairs with thymine by 2 hydrogen bonds, while guanine pairs with cytosine through 3 hydrogen bonds, each due to their unique structures.
Nucleotides also play a central role in metabolism at a fundamental, cellular level. They provide chemical energy for the many cellular functions that need it. Examples are: amino acid, protein and cell membrane synthesis, moving the cell and cell parts (both internally and intercellularly), cell division, and so on. In addition, nucleotides work in cell signaling, and they are in important cofactors of enzymatic reactions (e.g. coenzyme A, FAD, FMN, NAD, and NADP).
In experimental biochemistry, nucleotides can be labeled using radionuclides to make radionucleotides.
Voting
Voting is when a group of people decide something by saying what they want. It can be for electing a leader or representative, passing a law, and other things. When people are done voting, the votes are counted (often by machines) and the winner is determined.
Voting can be done in small groups (friends deciding what to do over weekend), societies (building committee deciding on whether to paint a building), nations (voting for president or - in some cases - voting for independence) and global (United Nations deciding how to limit nuclear weapon development).
Usually the side that gets most votes will win. This is called majority rule. The right to vote is called suffrage.
In some cases, a certain percentage may be needed to win a vote. This is often the case when voting to change the constitution of a country, or when electing a government official. When choosing a government official, there may be several rounds. In the first round, votes can be cast for all candidates. In the second round, only the two or three candidates with the most votes can be chosen.
Voting is done in democratic government.
Joule
A joule ( or sometimes ) is a unit in the SI system. It measures energy; usually in scientific or electrical appliances . It is named after James Prescott Joule.
A joule refers to the amount of energy transferred to an object when a force of 1 newton is applied on it over a distance of 1 metre (1J = 1N × 1m). It is related to the watt (a unit of power): one watt equals one joule per second.
It can also be understood as the work done for passing one ampere of Electric current through an Electric circuit of external resistance equivalent to one ohm for one second.
Carl Friedrich Gauss
Carl Friedrich Gauss (pronunciation: , Latin: Carolus Fridericus Gauss) (30 April 1777 – 23 February 1855) was a famous mathematician from Göttingen, Germany. Gauss contributed to many areas of learning. Most of his work was about number theory and astronomy.
He was born in Braunschweig. That city was then part of the duchy of Braunschweig-Lüneburg. Today the city is part of Lower Saxony. As a child, he was a prodigy, meaning he was very clever. When he was 3 years old, he told his father that he had incorrectly measured something on his complicated payroll. Gauss was correct. Gauss also taught himself to read.
When he was in elementary school, his teacher once tried to keep the children busy, telling them to add up all the numbers from 1 to 100. Gauss did it quickly, like this: 1 + 100 = 101, 2 + 99 = 101, 3 + 98 = 101, and so on. There were a total of 50 pairs, so 50 × 101 = 5,050. The formula is formula_1. According to this archived website, the problem given to Gauss was actually more difficult to do.
The Duke of Brunswick gave Gauss a fellowship to the Collegium Carolinum, where he attended from 1792 to 1795. This meant that the Duke paid for the education of Carl Friedrich Gauss at the Collegium. After this, Gauss went to the University of Göttingen, from 1795 to 1798.
When Gauss was 23, scientists spotted the asteroid Ceres but they did not see it for long enough to know its orbit. Gauss made calculations that let them locate it.
Later in life Gauss stopped working on pure math and turned to physics. He did work in electromagnetism and made an early electrical telegraph.
Gauss wrote Disquisitiones Arithmeticae which is a book about number theory. In that book he proved the law of Quadratic reciprocity. He also was the first mathematician to explain Modular arithmetic in a very detailed way. Before Gauss, mathematicians had used modular arithmetic in some cases but did not know much about using it broadly.
Gauss made important discoveries in Probability theory.
Grand Canyon
The Grand Canyon is a famous canyon in Arizona, formed by the Colorado River. It is a UNESCO World Heritage Site, and a National Park of the United States. It is also one of the Seven Natural Wonders of the World.