Prime purpose of this lecture is to present on Rockets and Satellites. A rocket moves forward when gases expelled from the rear of the rocket push it in the opposite direction. Hot gases are propelled out of the back of a rocket engine. The force of the gas in one direction (action) produces an opposing force (reaction) that propels the rocket forward. Satellites are used for communications, navigation, collecting weather data, and research, In addition, two-dozen Global Positioning Satellites give off signals that can be picked up by small receivers on earth. The receiver can then tell you where you are on earth’s surface.