Gumpowder to propel projectiles, was invented by the Chinese in the ninth century. One of the first texts to mention the use of rockets was the Huolongjing, written by Jiao Yu in the mid 14 th Century. In Europe, the first book on rocketry, was published by the Politsh-Lithuanian “Kazimierz Siemienowicz” and was entitled “Artis Magnae Artilleriae pars prima” which translates as “The Complete Art of Artillery” Here is a picture of a rocket which appeared in this early book!
Robert Goddard, is universally proclaimed as the father of “Modern Rocketry”. In 1917, the Smithsonian Institution gave him a grant to enable him to research rocketry. He attached a “de Laval” nozzle to a rocket motor to greatly improve its efficiency.
In this experiment, we will be working with ‘Solid Rocket Boosters’ This is where the propellant is made from a solid oxidiser and fuel. When rockets are launched into space, a combination of Solid Rocket Boosters and liquid Hydrogen and Oxygen fuel is often used to provide sufficient thrust. Rocket Motors:
De Laval Nozzle The De Laval Nozzle accelerates the hot gases coming from the burning charge to produce the thrust that propels the rocket skywards.
Rocket Motors: After ignition, the rocket motor generates ‘thrust’. The rocket begins to move quickly. Once the thrust- generating portion of the rocket motor has been burned there is a delay. The rocket coasts and consumes the momentum it has gained during the thrusting phase.
Rocket Motors: Different portions of The propellant inside the rocket motor fulfil different functions: Thrust: Provides the motion. Delay: Allows the rocket to “ coast”. Recovery Charge: Can be used to deploy a parachute.
Insert the igniter into the rocket motor Insert a plastic cap to retain the igniter in place and prevent it from falling out. CAREFUL: Not to break the fragile igniter! The wire that becomes hot when current is passed through is VERY fragile.
We use a stiff rod to launch our rockets from in order to keep them stable in the very first moments of flight when they are moving slowly.
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