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They can be connected to a light bulb or some other 'visible' means to indicate that someone it at the door.

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16y ago

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Why did Alexander Graham Bell work with deaf people?

Alexander Graham Bell followed the footsteps of his father, Alexander Melville Bell, as a teacher of the deaf. After graduating at the universities of Edinburgh and London, he spent his early years learning to educate deaf-mutes by using a system developed by his father. In 1872 he founded a school to train teachers of the deaf in Boston, MA. The school eventually became part of Boston University, where Bell was appointed professor of vocal physiology.


Was Alexander Graham Bell a philanthropist?

yes, he did a lot of work in helping the deaf.


Are Alexander Graham Bell's children deaf?

Alexander Graham Bell and his wife Mabel Gardner Hubbard had four children, two boys who died in infancy and two daughters... Elsie May Bell (1878 - 1864) and Marian Hubbard Bell (1880 - 1962). There is no indication that any of the children were deaf.


What did Alexander bell mother and father work as?

Alexander Graham Bell's father, Alexander Melville Bell, was a prominent teacher of elocution and phonetics, and he developed a system for teaching the deaf. His mother, Eliza Grace Symonds Bell, was also deaf and was a talented pianist. The family's focus on communication and sound influenced Bell's later inventions and work with the hearing impaired.


Were Alexander Graham Bell's daughter and wife deaf?

Bell had two daughters, but neither suffered from deafness. His wife Mabel was profoundly deaf, however, and Bell's mother had also been deaf-- one reason that motivated him in his work to develop a hearing aid that would restore some hearing to those who had lost it.


How much voltage is needed for a door bell to work?

12


Who were Alexander Graham bells family and what did they do?

bell's father,grandfather and brother had all been associated with work on elocution and speech,and both his mother and wife were deaf,profoundly influensing bell's life's work


Did Alexander bell have and brothers or sisters?

Alexander Graham Bell had two brothers, Melville and Edward, both of whom died from tuberculosis in their early adulthood. He also had a sister named Marion, who was deaf. Bell's family background, particularly his connections to the deaf community, significantly influenced his work and inventions in communication.


Did Alexander Graham Bell do sign language?

While Alexander Graham Bell did work with the deaf community and advocated for oralism (the use of spoken language over sign language), he himself did not communicate using sign language. Bell believed that deaf individuals should integrate into mainstream society by learning and using spoken language.


Why did bell invent telephone?

Alexander Bell was not trying to invent the telephone . . . he was inventing a device that would help deaf people hear a little bit. He ran wires into a different room where helper was listening. It worked! The helper heard Bell from the other room. That started the idea that the device would work at a far distance from the person speaking.


Why did alexandre bell invented telephone?

Alexander Bell was not trying to invent the telephone . . . he was inventing a device that would help deaf people hear a little bit. He ran wires into a different room where helper was listening. It worked! The helper heard Bell from the other room. That started the idea that the device would work at a far distance from the person speaking.


Who raised Alexander Graham Bell?

Alexander Graham Bell was raised by his parents, Alexander Melville Bell and Eliza Grace Symonds Bell. His father was a prominent teacher of the deaf, which greatly influenced Bell's future work in communication technology. The family environment, steeped in the study of speech and sound, played a significant role in shaping Bell's interests and innovations.