Science & Mathematics Questions & Answers

Science & Mathematics Questions & Answers

What is a nocebo?

Nocebo is an inert drug which when administered to a patient causes harmful effects in her, not because of any inherent chemical characteristics, but because she has negative feelings about it. It’s the opposite of a placebo, a sugar pill supposed to produce a therapeutic effect because the patient has faith in the drug or doctor administering it. In Latin, …

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What is a mirage?

Mirages are optical illusions produced by extraordinary atmospheric conditions. They can be non-existent sheets of water or similar visions, inverted or oversized images of distant objects or various other distortions. All are caused by the refraction, or bending, of light rays as they pass through two layers of air with different densities. The differences in density are usually due to …

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What is a micelle?

A micelle is the cluster or aggregated particles formed by associated colloids (substances which, at high concentration, behave as colloidal solutions due to formation of micelles) in solution. Micelle formation takes place above a certain concentration called Critical Micellization Concentration (CMC) and above a particular temperature called Kraft Temperature. Every micelle system has a particular value of CMC. Micelles are …

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What is a memristor?

Memristor is claimed to be the fourth basic element to electrical circuit theory along with the capacitor, resistor and inductor. It was recently discovered in HP Labs. It’s most interesting characteristic is that it remembers the amount of charge that flows through it. So, it is named as memory resistor or memristor. Researchers believe the discovery will pave the way …

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What is a mammal?

People are mammals, and so are lions, elephants, whales, pigs and rabbits. How do we know? Well, scientists have sets of rules which tell them what sort of animals creatures are: whether they are mammals, fish, reptiles, amphibians, birds or insects. There are two things which tell the scientists that an animal is a mammal. Firstly, all mammals have some …

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What is a magnet?

A magnet is a piece of iron which will attract or repel pins, tacks, nails or anything else made of that metal. The word comes from a district in Thessaly, Greece, called Magnesia. It was here that men first noticed that certain black stones attracted iron. These stones were composed of an iron ore called magnetite and were natural magnets. …

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What is a light year and how long is it?

A light year is a way of measuring distance. I know that doesn’t seem to make much sense because “light year” contains the word “year,” which is normally a unit of time. Even so, a light year measure distance. When astronomers use their telescopes to look at the planets and the stars, the distances are gigantic. For example, the closest …

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What is a kymograph?

Kymograph is an electrical device used in preclinical medical research to record the biological responses (muscular motion, change in BP, and other physiological phenomena) of various tissues. It was invented by Carl Ludwig (1847) to record the change in arterial BP. It consists of an electrically driven gear box with a vertical spindle carrying a drum, and is disengaged before …

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