The Safety Helmet
Yes it did.
The Ba-rings will be heavy and it will spin a little bit slower than the other without the lead, most of them have lead in them though. If any grey areas are exposed, you can rub them on paper to see if there is transfer. Lead is soft and can be used to mark on paper.
all inventions and any discovery has both positive and negative effects even if we don't know it that's just a fact of life. for example the electronic/mecanical assembly line the positive is that it creates even faster and similar items the negative is it puts alot of people out of a job
Nikola Tesla was a genius and the best inventor of the time but he had no mind as a seller. In 1893 he came out with a remote controled boat. He tried to sell it to the navy as a weapon againts ships and thus blowing them with explosives. The navy said no. He didn't think that this remote controled boats would make a best selling toy. But everybody liked Tesla's inventions. The electric starters for cars made it easy for us since cars back them had to be crancked manualy. The alternate current motor is the basis of all the electricity used today in homes. The coil is the basiss of any wireless communication system. The list is long but the people liked Tesla's inventions.
NOTHING!
yes
Yes it did.
Yes it lead to the discovery of computers and videogame consoles
um, it has led steamboats to become more successful and ledsteamboats to become more modern and FANCY !
no no no no no no no no no no
no.
Yes it was.
no
yes
Eli Whitney's invention of the cotton gin actually changed the face of American agriculture. It lead to the invention of the McCormick Reaper and eventually to many more mechanized agricultural tools.
no i don't think so
Sarah Boone was awarded the patent for the ironing board but did not create any other inventions that were patented at the time. Her life is actually somewhat of a mystery.