86. Who invented the first electric generator?
a) Michael Faraday
b) Thomas Edison
c) Nikola Tesla
d) George Westinghouse
Answer: a) Michael Faraday
87. Who discovered the phenomenon of radio waves?
a) Heinrich Hertz
b) James Clerk Maxwell
c) Guglielmo Marconi
d) Nikola Tesla
Answer: a) Heinrich Hertz
88. Who invented the first successful submarine?
a) John Philip Holland
b) Robert Fulton
c) David Bushnell
d) Cornelius Drebbel
Answer: a) John Philip Holland
89. Who discovered the law of specific heats?
a) Joseph Black
b) James Clerk Maxwell
c) Heinrich Hertz
d) Robert Boyle
Answer: a) Joseph Black
90. Who invented the first successful electric motor?
a) Michael Faraday
b) Thomas Edison
c) Nikola Tesla
d) George Westinghouse
Answer: a) Michael Faraday