Fireworks! Bright lights and big bangs!
Everybody has been to the Detroit Fireworks! If you haven't your missing out on a wonderful experience! But does anybody know How fireworks work???
Lets start with History! • The discovery of fireworks, or namely the formulation of gunpowder is believed to have occurred by chance approximately 2,000 years ago in China. • It is thought that a Chinese cook accidentally mixed three common kitchen ingredients:KNO3,Sulfur,and Charcoal • These were heated over a fire and dried to give a black flaky powder which burned with a loud bang when ignited. This crude, early mixture has come to be known in our modern world today as gun powder.
Gunpowder • The Chinese named this fascinating black powder and developed it further. The mixture was inserted into the hollow of a bamboo stick and when thrown into a fire, the gases produced by the ignited burning powder inside caused an build up of pressure and blasted the tube apart. The basic fire cracker was born.
Taking it Futher • It was in 1560 that European Chemists managed to make gunpowder as explosive as possible by experimenting with the ratios of the ingredients. The final proportion was set as follows: • 1) Salt Peter 75%2) Charcoal 15% 3) Sulphur 10% These ratios are still used today some 500 years later. • It was Italians who were able to develop aerial shells that launched upward and exploded into a fountain of color; lighting up the night sky to the enjoyment of onlookers.
Light and Color • Fireworks have lit up the night sky for centuries however, color is an invention that has only been introduced into displays in the last 100 years. • Before the 19th Century, the only colors that could be produced were yellows and oranges with the use of steel and charcoal. Later development involved Chlorates which introduced basic reds and greens to the repertoire. Good blues and purples were not developed until this century and the quest for the formation of a deep forest green colored firework continues still to this day.
Incandesence and Luminescence Color production in fireworks involves two main mechanisms: • 1) Incandesence2) Luminescence • Incandescence is the light produced from heat. Heat causes a substance to grow hot and glow. This results in the emission of infrared, then red, orange, yellow, and white light as the substance grows increasingly hotter. • Luminescence is light produced using energy sources other than heat. This involves the absorption of energy by an electron of an atom or molecule thereby causing it to become excited but also unstable. As the electron drops back down to its ground state, energy is released and in this case, it is in the form of light as the energy is released in the form of a phonon. The energy of the phonon determines its wavelength and color.
Construction • Sights such as the that pictured above originate from small shells. They are reliant on lift charge in order to propel the shell into the air. This process is kick started by use of a time fuse which leads up to the shell causing it to explode. • The energy from this propels the shell containing black powder and star pellets from the launch tube into the air. Attached to this is a Time delay fuse which is the source of the final explosion where the stars are released into the sky.
The Future Of Fireworks! • Computers now play a hugely important role in both the development of fireworks and the designing of their displays. Computer programmers can be used to synchronize the firing of thousands of fireworks from just one control panel known as a "firing panel".
How Does This Work? • The firework is fitted with a metal match head which resembles that of a real match. When the button from the firing panel is pushed, a surge of electrical charge or current is created and travels down a thin wire until it hits the match head and ignition takes place (just as a regular match would ignite when struck). The spark from this ignition lights a fuse to the firework causing it to elevate into the air. • It is this method of technology that is increasingly used by pyrotechnicians today and it is most certainly used in large scale displays such as those presented over the millennium.
REFERENCES! • www.pyrouniverse.com/consumer/howtheywork.htm • www.stop-fireworks.org/composition.htm • www.fireworkstheory.net/device.html Thank You