Question 41 :
What invention is credited to the Russian born American inventor Vladimir Kosma Zworykin?
Zworykin invented both the tube (iconoscope) for transmission and the receiver (kinescope) in 1923 and 1924, respectively.
Question 42 :
Benjamin Franklin was a prolific inventor. He invented the lightning rod, the Franklin stove, studied electricity, discovered the Gulf Stream, started the first library, and on and on. Among his many other inventions, what musical instrument did he invent?
Ben also holds a lot of firsts - first U.S. ambassador, first political cartoonist, first American philosopher, organized the first fire department, and on and on.
Question 43 :
What Thomas Davenport invented?
Invented in 1834.
Question 44 :
What Elisha Otis invented?
In 1853, American inventor Elisha Otis demonstrated a freight elevator equipped with a safety device to prevent falling in case a supporting cable should break. This increased public confidence in such devices. Otis established a company for manufacturing elevators and patented (1861) a steam elevator.
Many people think that he invented the elevator, but the truth is, he invented the elevator brake. He also invented the railway safety brake.
Question 45 :
Where was the yo-yo invented?
The yo-yo was first used by hunters as weapons. They were wooden disks on strings. In the 1920s, a man from the U.S. named Donald Duncan made the yo-yo into a toy after he visited the Philippines.