Category Science & Technology

When was fire discovered?

Fire has been known to man since the earliest times. Archaeologists have found evidence of charcoal and charred remains of bone amongst stones, dating back thousands of years.

It is likely that early man knew how to use fire before he understood how to create. If, for example, lightning struck a tree and set it alight, man would have had the use of the fire and would have been able to keep it going.

Cavemen would have noticed sparks created when they trampled on loose stones. It is unlikely though, that they would have immediately understood that the friction of two stones rubbing together created the sparks. It may have been generations before this idea was put into practice. Almost certainly the first fires that man experienced would have started by accident or as the result of nature, hence the lightning idea.

Fact file

Coke is a fuel produced by roasting coal in large ‘coke ovens’ at extremely high temperatures. In these ovens, there is not enough oxygen for the coal to burn; instead, it is roasted which removes gases and leaves the almost pure carbon called coke.

 

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When did the Chernobyl disaster occur?

On 25-26th April, 1986 a serious accident occurred at the Chernobyl nuclear power station in the Ukraine. Some technicians in the power station attempted a poorly devised experiment. In doing this they shut down the reactor’s safety system. The reactor continued to be powered, but in a dangerous state. The chain reaction in the core of the reactor led to a massive explosion, and radiation was emitted in huge quantities. Contaminated clouds carried the radiation not just over parts of Russia, but over the rest of the world.

Fact File

In the 1970s, organizations such as Friends of the Earth and Greenpeace began to campaign on many environmental issues. These included nuclear weapons, destruction of the rainforests, and dumping of toxic waste.

 

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When were nuclear weapons first used?

Nuclear weapons were first used in 1945, at the end of World War II. Two bombs were dropped on the Japanese cities of Hiroshima and Nagasaki by the USA.

Hundreds of thousands of people were killed as a result of these two bombs, leaving a trail of destruction never seen in war before.

This was not only an important turning point in history. Nuclear bombs became a new, deadly threat with huge, a destructive consequences. The nuclear age had begun.

Fact File

In 1962 the Cuban crisis erupted when the USA discovered that the USSR was building missile sites on the island of Cuba in the Caribbean. The two superpowers came to the brink of war before the USSR agreed to withdraw the weapons.

 

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When did gold mining begin?

Although the time cannot be pinpointed exactly, it is widely believed that gold mining dates back about 5,000 years. The first gold was mined in Egypt, and wall paintings have been found which show gold mining in its various stages of production. Gold was extracted (panned) from river water; this was achieved by sifting out the lighter sands in the water to leave the heavier, gold particles behind. By 3,000 BC gold rings were used as a form of payment. With the exception of coins, gold was used only for decorative purposes.

Around 2,000 BC mine shafts were constructed to obtain gold found in ores deep in the ground; the Greeks and Romans became particularly good at this.

Fact File

The gold standard was a monetary system in which the standard unit of currency is a fixed quantity of gold. It was first put into operation in Great Britain in 1821.

 

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When was the hovercraft invented?

The hovercraft was invented in 1955 by the British scientist Christopher Cockerell. He decided to solve a problem that had been baffling scientists for 80 years. In the 1870s, the British engineer John Thornycroft began to design a ship that moved along on a cushion of air to reduce friction between the ship’s hull and the water. He was unable to work out how to contain the cushion of air under the boat, but Cockerell solved this by attaching a rubber skirt to the bottom of the boat. This idea worked perfectly and the hovercraft was born.

Fact File

A boat is a pretty large object, yet it floats easily on the surface of water. This is because the fluid actually holds it up. The liquid offsets the force of gravity. If you want to feel this force, just take a blown-up beach ball into water. The water seems to push up the ball.

 

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When was the first aeroplane flight?

The first ever powered, sustained and controlled aeroplane flight took place at Kitty Hawk, North Carolina, USA, on December 17, 1903.

Orville Wright and his brother Wilbur both designed and built the plane for this historic flight. Orville piloted the first flight in the aircraft, aptly named the Flyer. He travelled 120 feet through the air in 12 seconds; Wilbur managed 175 feet in 12 seconds straight after this.

They each had one more attempt: Orville flew 200 feet in 15 seconds, before Wilbur recorded the longest flight of the day, travelling 852 feet in 59 seconds.

Fact File

Concorde is a supersonic airliner. The sonic ‘boom’ it produces, together with noise and air pollution concerns, has limited the development of such aircraft.

 

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