1. Who invented Helicopter ?

Answer:

Igor Sikorsky

2. Who invented Atomic Bomb ?

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

3. Who invented Electron ?

Answer: Thomson. J of Britain in 1897

4. Who invented Stainless Steel ?

Answer: Harry Brearley of Britain in 1913.

5. Who invented Ballistic missile ?

Answer: Wemher von Braun of Germany in 1944.

6. Who invented Neutron ?

Answer:

JAMES CHADWICK in 1932

7. Who invented Proton ?

Answer:

Ernest Rutherford