Sunday, 30 January 2011
Can you use water to launch a rocket?
Begin the test by turning the handle. The lights will turn green when the rocket is ready to launch. Press the button to initiate the countdown.
The rocket launches into the air once the gases generated by the turning of the handle are ignited.
The electric current created by the turning of the handle breaks down the water molecules H2O into gaseous elements, hydrogen (H) and oxygen (O). This chemical reaction is endothermic in nature, in other words, it requires energy, which in this case comes from the muscles of the person turning the handle. The reverse reaction, in which the hydrogen and oxygen are fused, in other words, the combustion of hydrogen into water, is correspondingly exothermic, meaning that it releases energy. As the gas mixture explosively combusts and turns into water vapour, pressure forms in the combustion chamber. The pressure releases as the combustion gases flow with force out from the end of the rocket, thereby causing the rocket to lift.
The thermal value of the burning hydrogen in relation to its mass is very high. It is about three-fold in comparison to that of petrol. Hydrogen serves as the fuel for space rockets, because any extra weight in the rocket would be detrimental to its takeoff. The hydrogen, and the oxygen required for it to combust, are placed into the rocket as cooled liquids, each in its own separate tank.