Who invented the microphone?
Answer: B
Alexander Graham Bell is credited with it.
His liquid transmitter of 1876 varied the resistance of a circuit with the sound waves striking a diaphragm. Emile Berliner and David Hughes developed the carbon microphone soon afterwards, and Edison improved it for telephone use.
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Who invented waterproof rubberised cloth?
Answer: D
Charles Macintosh invented it.
The Glasgow chemist found in 1823 that naphtha, a waste product of the gasworks, dissolved rubber, and sandwiched the solution between two layers of cloth. The waterproof coat still bears his name, with an added k.
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First combine harvester was invented in 1834 by
Answer: A
Hiram Moore invented it.
He patented the combine harvester in Michigan in 1836, a machine that reaped, threshed and winnowed in one pass. Early versions were drawn by teams of up to forty horses.
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Who discovered oxygen?
Answer: C
Joseph Priestley discovered it independently.
He isolated the gas in 1774 by focusing sunlight on mercuric oxide, and called it dephlogisticated air. Scheele had prepared it earlier but published later, and Lavoisier named it and explained its role in combustion.
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The theory of inheritance of acquired character was propounded by
Answer: A
Jean-Baptiste Lamarck propounded it.
He held in 1809 that characters acquired in a lifetime - the giraffe's neck stretched by reaching - are passed to offspring. Weismann disproved it by cutting off the tails of mice for generations without effect, and Darwin's natural selection replaced it.
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Crescograph is an instrument to record
Answer: C
The crescograph records plant growth.
Jagadish Chandra Bose invented it about 1900. It magnified movement up to ten thousand times, letting him show that plants respond to light, heat and touch, and that their growth proceeds in tiny pulses.
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First mechanical calculator was built in 1642 by
Answer: B
Blaise Pascal built it.
He made the Pascaline in 1642 at nineteen to help his father, a tax official, with his accounts. It added and subtracted by geared wheels with automatic carry, and about twenty were made.
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The World Wide Web was first made public by which English computer scientist?
Answer: B
It was Sir Tim Berners-Lee.
He proposed a hypertext system at CERN in 1989 and wrote the first browser and server the following year. He gave the technology away, and CERN placed it in the public domain in 1993.
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Who invented the BALLPOINT PEN?
Answer: A
The Biro brothers invented it.
Laszlo Biro, a Hungarian journalist, and his brother Gyorgy, a chemist, patented the ballpoint in 1938, using the quick-drying ink of newspaper presses in a pen tipped with a rolling ball. In much of the world the pen is still called a biro.
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Inventor who invented vulcanized rubber that is made by mixing latex with sulphur and is then heated is
Answer: A
Charles Goodyear invented it.
He found in 1839 that rubber heated with sulphur stayed elastic in heat and cold alike, instead of melting in summer and cracking in winter. The process is named after Vulcan, the god of fire.
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