Rockets or Launch Vehicles:
Every flight into space begins with a rocket launching. The rocket can lift a satellite or spaceship carrying human beings and equipment into space. Therefore, it is also called launch vehicle. The rocket has been known to mankind for centuries. Rockets used as firecrackers are a common sight on festive occasions in our country. But the rockets that launch space whicles use highly advanced technology, and, of course, they are far more
When the fuel in the rocket is set tofire, a stream of hot gases is expelled at a high speed from its rear end (Fig). As ireaction to the thrust of the,gases, the rocket moves in the opposite direction. As long as the fuel in the rocket burns, shooting out gases, the rocket continues to accelerate forward, and acquires great speed. No single rocket fired from the earth can attain in one go the high speeneeded to orbit the earth, or to escape its pull. Higher speeds are reached by using big and small rockets, in stages. in the launch vehicle. As the large rocket soars into space and uses up its fuel, lt IS separated from the smaller rocket and drops off. The smaller rocket already going at high speed is then fired to accelerate it to an even higher speed. Three-stage rockets are usually able to achieve speeds suitable for most purposes in space (Fig). The final stage of the launch vehicle carries the payload. Activity Verify the principle of rocket motion by releasing an inflated balloon with its neck open. The different kinds of payloads that rockets carry into space include artificial satellites and space probes to nearby heavenly bodies. The satellites and probes themselves carry communication and research Quipment.