Air conditioning is used for the purpose of removing heat from air to provide cooling within a building. It can also be used to change humidity, air movement, air purification, or ventilation.
Air conditioning has been used since the ancient Egyptians covered their windows with wet reeds to cool the air coming in to their houses. Mechanical cooling systems in the 1920s proliferated, enabling migration to the Southeast and Southwest parts of the US known as the Sun Belt.
The jet engine was invented in the first century AD as the aeolipile, or Hero's engine. This device was a ball containing water and two jet nozzles at either edge of the ball. When the water was heated to boiling point, steam came out of the nozzles and the ball rotated.
Englishman Frank Whittle suggested using a gas turbine turbojet to power aircrafts in 1928, creating the first liquid fuelled engine in 1937. Without the jet engine, jet aircraft, rocket engines, spaceflight and missiles would not have been possible.
Zhang Heng invented the world's first Earthquake detector, or seismometer in the first century AD. His detector was based on the principle of inertia. When a tremor was detected, a bar inside the seismoscope would move horizontal pins which dropped a bronze ball from one of eight dragon heads into the mouths of metal toads underneath.
The device had eight arms and projections representing the direction of the seismic wave. Modern seismographs can give early warning of approaching seismic P and S waves for alerts can be sounded so people can get to safety.
In the 15th century Leonardo da Vinci wrote about air tanks that could be used to breathe artificially under water. He also designed an immersion kit with snorkels, a glass mask for air, and a float on the jacket. The suit was to be made from pigskin which was treated with fish oil to make it water resistant.
Without the ability to breathe underwater with a Self-Contained Underwater Breathing Apparatus (scuba) suit we would not be able to work on offshore construction projects, rescue missions or see the undersea world on holiday.
The power loom was invented in 1785 by Edmund Cartwright the English inventor. Before mechanisation the horizontal weft thread had to be manually passed from end to end before the next line of fabric could be woven.
The introduction of the flying shuttle and mechanisation paved the way for the Industrial revolution in the 18th century.
An induction motor uses electromagnetic induction to produce rotary torque. If you hold your right fist out with your thumb extended, you can predict the direction of current flow (thumb direction) from the rotation of your fingers towards the fingernails (right hand grip rule).
Nikola Tesla is widely credited with producing the first working model of a motor in 1887. The first Alternating Current alternator was built by Hyppolyte Pixii in 1832.
Combustion of fuel occurs when air (or another oxidising gas) is introduced into a combustion chamber. The resulting expansion of the combustion gas forces an object, like a piston or turbine blade to move.
Intermittent (four-stroke) combustion engines are found in cars whilst two-stroke engines are commonly found in small motorbikes, and petrol driven lawnmowers.
The term turbine comes from the Latin word turbo which means a vortex. A turbine is a rotary mechanical device that extracts energy from a flow such as steam (boilers), water (hydroelectric dams) or air (jet engines) and converts it into propulsion, motion or energy.
The steam turbine was invented by British Engineer Sir Charles Parsons who invented the reaction turbine and Swedish engineer Gustaf de Laval who invented the impulse turbine.
Furnaces are used to heat objects inside to extremely high temperatures. Furnaces are used to melt iron ore and produce pig iron, make steel and forge metal items.
Modification in furnace design enables clay to be baked at high temperatures to make bricks, pottery, ceramics and make glass from sand.
The sewing machine has revolutionised the world. It was invented by a British man, Thomas Saint in 1790. It took away the time consuming and laborious task of dressmaking by automating the stitching mechanism.
The machine uses a series of gears, motors, pulleys and guides to bring the thread through to the cloth. A shuttle and bobbin rotate, pulling the thread from above and locking it around the thread from below. Think of all of the clothes in your wardrobe and furnishings in your home. Now imagine making them all yourself by hand.