Science & Mathematics Questions & Answers

Science & Mathematics Questions & Answers

How are Stem Cells stored?

Stem cells, which hold the promise of new cell-based therapies to treat critical medical conditions, have to be effectively stored until it’s time to use them. The method is called cryopreservation: it freezes stem cells at temperatures below -150 o C, by immersing them in nitrogen vapour. But if the cells are to survive this process, they need to be …

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How are points in a stock exchange calculated?

Points or index refers to a figure indicative of the health of the stock market. The most widely used index is sensex or sensitive index which is based on weighted value of 30 numbers of most traded shares in the Mumbai stock exchange. Each stock has a percentage share in a total of 100 and affects the value of the …

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How are international telephone dialling codes assigned to countries?

International Telecommunication Union (ITU) recommendation defines the international public telecommunication numbering plan used in the PSTN. It also defines the format of phone numbers. As per these recommendations, numbers can have a maximum of 15 digits and are usually written with a + prefix. CCITT, the predecessor of the ITU Telecommunication Standardization Sector, developed the first formal list of telephone …

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How are electric pylons placed across mountains to transmit electricity?

Electric pylons are tall supports – made of galvanised steel lattice, steel tube or wood – used for power line construction. In normal terrain, they are assembled on the site. In mountainous regions, helicopters are used for power line construction, which are efficient but expensive. In the aerial construction method, the entire structure is pre-assembled and shifted in helicopters.

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How are Deaf-mutes taught to speak?

How are Deaf-mutes taught to speak?

It was not before sixteenth century, an Italian doctor named Jerome Cardan got the idea of teaching deaf-mutes through written characters. As a result of his work finger alphabets were developed, similar to the finger alphabets used today. With the help of finger alphabets, a deaf-mute makes the letters with his fingers and spells out words. He also depends on …

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How are corrective lenses made?

The lab technician selects a lens blank that has the correct segment (called an add) and a base curve close to the prescribed power. Then to make the power match the prescription exactly, another curve is ground on the back of the lens blank. In most labs, the equipment is designed to grind minus curves, so a strong, plus lens …

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How 3-D Glasses Work?

Although the 1950s are most often considered the 3-D movie decade, the first feature length 3-D film, “The Power of Love,” was made in 1922. Since that time the use of 3-D technology in theaters and on television has drifted in and out of mainstream popularity. But, whether you’ve used them for the big screen or at home in front …

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Has the Sun stopped burning?

Believe it or not, a tank of cleaning fluid buried underground is telling us about what goes on at the center of the Sun. and the startling news is that the Sun may have stopped burning, albeit temporarily. According to theory, the nuclear reaction include the Sun should produce atomic particles known as neutrinos, which escape directly into space and …

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Hairy star terrorizes the world!

The ancient Greeks called them ‘hairy stars’. In fact, they were seeing comets-heavenly bodies with long, streaming tails that travel endlessly around the sun. Before they were understood, comets were believed to foretell plagues, war and death. A comet was seen over Rome after the murder of Julius Caesar in 44 B.C. Another, Halley’s comet, appeared over Europe in 1066, …

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