1. Who invented Safety Pin ?

Answer: Walter Hunt of U.S.A. in 1849

2. Who invented Machine Gun ?

Answer:

Helge Palmcrantz, Swedish inventor and industrialist

3. Who invented Laser ?

Answer:

Charles H. Townes

4. Who invented Electron ?

Answer: Thomson. J of Britain in 1897

5. Who invented Relativity Theory ?

Answer: Einstein of Germany in 1905.

6. Who invented Automatic rifle ?

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

7. Who invented Nylon ?

Answer:

Wallace Carothers