1. Who invented Air Conditioning ?

Answer:

Willis Carrier in 1902

2. Who invented Stethoscope ?

Answer: Laennec of French in 1819.

3. Who invented Floppy disk ?

Answer: IBM in 1970

4. Who invented Transistor ?

Answer: Bardeen, Shockley & Britain of U.S.A. in 1948

5. Who invented Dynamo ?

Answer:

Hypolite Pixii of France in 1832

6. Who invented Automatic rifle ?

Answer: John Browning of U.S.A. in 1918.

7. Who invented Optical Fibre ?

Answer:

Indian-born American physicist Narinder Kapany