1. Who invented by Electric Lamp ?

Answer: Thomas Alva Edison of U.S.A. in 1879

2. Who invented Steam Engine (Piston)

Answer: Thomas Newcomen of Britain in 1712

3. Who invented Submarine ?

Answer:

John Philip Holland

4. Who invented Stainless Steel ?

Answer: Harry Brearley of Britain in 1913.

5. Who invented Hydrogen bomb ?

Answer:

Edward Teller

6. Who invented Nylon ?

Answer:

Wallace Carothers

7. Who invented Floppy disk ?

Answer: IBM in 1970