Physics Inventions — Set 4
Inventions · भौतिकी के आविष्कार · Questions 31–40 of 70
The first mechanical calculator, known as the 'Pascaline', was invented by?
Correct Answer: B. Blaise Pascal
Blaise Pascal invented the mechanical calculator in 1642 to help his father with tax work. It could perform addition and subtraction directly using a series of gears. Only about twenty of these machines were actually produced.
Who is the inventor of the first practical electric fan, introduced in the 1880s?
Correct Answer: D. Schuyler Wheeler
Schuyler Wheeler invented the two-blade personal electric fan in 1882. He was a prominent American engineer who also worked with Edison. His invention provided an affordable way to stay cool indoors.
The first synthetic fiber, Nylon, was invented by a team led by?
Correct Answer: D. Wallace Carothers
Wallace Carothers developed Nylon while working for the DuPont company in 1935. It was the first completely synthetic fiber to be used in clothing. It became famous for its use in hosiery during World War II.
Who invented the first modern internal combustion engine using the 'Otto Cycle'?
Correct Answer: B. Nikolaus Otto
Nikolaus Otto developed the four-stroke internal combustion engine in 1876. This 'Otto Cycle' is the basis for most gasoline engines used in cars today. His work revolutionized land-based transportation and power.
The first practical submarine, the 'Turtle', was invented by whom in 1775?
Correct Answer: B. David Bushnell
David Bushnell built the Turtle during the American Revolutionary War. It was a hand-powered, egg-shaped vessel intended to attach bombs to enemy ships. It was the first submarine used in actual combat operations.
Which scientist invented the first stethoscope using a wooden tube?
Correct Answer: A. René Laennec
René Laennec invented the stethoscope in 1816 in France. He wanted to listen to the heart sounds of patients more clearly and comfortably. This invention is now a standard tool for doctors worldwide.
The ballpoint pen was invented and popularized by?
Correct Answer: D. László Bíró
László Bíró, a Hungarian journalist, patented the first successful ballpoint pen in 1938. He used a tiny ball bearing and thick ink to prevent leaking. The term 'biro' is still used in many countries to mean a pen.
Who invented the first successful electric telegraph system in the United States?
Correct Answer: B. Samuel Morse
Samuel Morse co-developed the Morse code and the telegraph in the 1830s. The first message sent was 'What hath God wrought' in 1844. This system allowed for almost instantaneous communication across continents.
The safety pin was invented and patented by which American inventor in 1849?
Correct Answer: B. Walter Hunt
Walter Hunt invented the safety pin to settle a fifteen-dollar debt. He sold the patent rights for only four hundred dollars to pay off his creditor. He also invented the first functional sewing machine but did not patent it.
Who is the inventor of the first practical refrigerator using vapor-compression?
Correct Answer: A. Jacob Perkins
Jacob Perkins was the first to patent a practical vapor-compression refrigeration cycle. However, James Harrison later built the first commercial ice-making machine in Australia. This technology ended the reliance on harvested natural ice.