1. Who invented Steam Engine (Piston)

Answer: Thomas Newcomen of Britain in 1712

2. Who invented Refrigerator ?

Answer:

Oliver Evans in 1805

3. Who invented Hydrogen bomb ?

Answer:

Edward Teller

4. Who invented Atomic Bomb ?

Answer: J. Robert Oppenheimer of U.S.A. in 1945

5. Who invented Periodic table ?

Answer:

Dmitri Mendeleev invented Periodic Table

6. Who invented paper ?

Answer:

Cai Lun

7. Who invented Stainless Steel ?

Answer: Harry Brearley of Britain in 1913.