1. Who invented Helicopter ?

Answer:

Igor Sikorsky

2. Who invented Steam Engine (Condenser)

Answer: James Watt of Britain in 1765

3. Who invented Vitamin C ?

Answer:

Scottish naval surgeon James Lind in 1747

4. Who invented Atomic theory ?

Answer: Dalton of Britain in 1803.

5. Who invented Neutron bomb ?

Answer:

Samuel T. Cohen

6. Who invented Refrigerator ?

Answer:

Oliver Evans in 1805

7. Who invented Atomic Bomb ?

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