by Nithya[ Edit ] 2010-01-28 21:49:26
Do you know how rockets are moving against gravitational force?? It is due to the ejection of fluid. It ejects the fluid in a fast manner. First rocket was launched in the thirteenth century but by the end of twentieth century human beings started traveling in rockets successfully. Rockets are also used in fireworks. Day by day the rockets are prepared in light weight and in efficient manner. They are becoming powerful day by day.