Inventions — Set 6
Physics · आविष्कार · Questions 51–60 of 60
Who invented the thermometer scale where water freezes at 0 degrees and boils at 100 degrees?
Correct Answer: A. Anders Celsius
Anders Celsius proposed a centigrade scale for measuring temperature in 1742. Originally, he set 0 as the boiling point and 100 as the freezing point. The scale was later reversed to the modern version used in most countries today.
The invention of the microscope is generally attributed to which inventor?
Correct Answer: C. Zacharias Janssen
Zacharias Janssen is often credited with creating the first compound microscope around 1590. Antonie van Leeuwenhoek later significantly improved lens quality to see bacteria and cells. This invention opened up the previously invisible world of microbiology to scientists.
Which inventor developed the first practical submarine, the 'Turtle'?
Correct Answer: B. David Bushnell
David Bushnell built the 'Turtle', the first submarine used in combat during the American Revolution. It was a small, hand-powered vessel designed to attach explosives to enemy ships. Although its missions were unsuccessful, it proved that underwater navigation was possible.
Who invented the fountain pen with an internal ink reservoir?
Correct Answer: D. Lewis Waterman
Lewis Waterman patented the first reliable fountain pen using a capillary feed system. This design prevented the ink from leaking or blotching while writing on paper. Before this invention, people had to constantly dip pens into inkwells.
The invention of the ballpoint pen is credited to?
Correct Answer: C. Laszlo Biro
Laszlo Biro developed a pen that used a tiny rolling ball to transfer quick-drying ink. This design solved the problem of ink smudging and leaking common in fountain pens. The 'Biro' became so popular that the name is used for pens in many countries.
Who invented the first practical sewing machine?
Correct Answer: A. Elias Howe
Elias Howe patented the first sewing machine using a lockstitch design in 1846. Isaac Singer later improved the machine by adding a foot treadle for hands-free operation. This invention revolutionized the garment industry by making clothing production much faster.
The invention of the lead-acid battery is credited to?
Correct Answer: C. Gaston Plante
Gaston Plante invented the first rechargeable battery using lead plates and sulfuric acid. This type of battery is still widely used in cars for starting engines. It was the first battery that could be recharged by passing a reverse current through it.
Who invented the first functional electric motor?
Correct Answer: C. Michael Faraday
Michael Faraday demonstrated electromagnetic rotation, which is the principle behind the electric motor. He showed that a wire carrying a current would rotate around a magnetic pole. His discoveries in electromagnetism formed the basis for all modern electric power technology.
The invention of the cotton gin, which cleaned cotton fiber from seeds, was by?
Correct Answer: C. Eli Whitney
Eli Whitney invented the cotton gin in 1793 to automate the removal of seeds from cotton. This machine greatly increased the speed and profitability of cotton production in the US. However, it also led to an increased demand for labor on plantations.
Who is credited with the invention of the first practical air conditioner?
Correct Answer: A. Willis Carrier
Willis Carrier designed the first modern air conditioning system to control humidity in a printing plant. He realized that cooling air also removed moisture from it, improving print quality. This invention eventually made living in hot climates much more comfortable for millions.