•
He painted the “Mona Lisa” and used water to power many of his experiments:
Superstars of
science
Leonardo da Vinci
•
Once said: “Water is the driving force of all nature”
and “The noblest pleasure is the joy of understanding.”
•
He lived in Italy in the 15th century.
•
He was an anatomist, an architect, a sculptor, an inventor,
an engineer, a painter, and a musician — in short, a
universal genius.
LEONARDO’S INGENIOUS INVENTIONS
•
A water-propelled mechanical saw, which made splitting thick tree trunks much easier
•
A paddle boat propelled by pedals, at a time when all other boats used oars
•
A swing bridge that could be rotated to one side to allow large ships to travel on rivers
Archimedes
•
He shouted “Eureka” as he ran naked through the streets of the cit
y
after discovering Archimedes’ principle while taking a bath.
•
He was born in Greece in 287 BC.
•
He was quite possibly the world’s first physicist.
THE LEGEND OF THE GOLDEN CROWN
Legend has it that a king called Hiero once commissioned a goldsmith to fashion a
new crown made from pure gold. Once finished, the golden crown weighed exactly
the same as the lump of gold that the king had given the goldsmith in order to create the cr
own.
However, the king still suspected that the goldsmith had deceived him. He called on Ar
chimedes and asked him to verify
the purity of the crown, without damaging it in any way. Archimedes pondered this difficul
t task for a long time.
Then, as he was taking a bath, he was struck with a flash of inspiration. Gold was the heaviest known met
al at that
time. This meant that a piece of gold weighing exactly the same as a piece of another met
al would have a smaller
volume. Archimedes therefore concluded that if the goldsmith had substituted some of the gol
d for some other metal in
the crown, that the crown, when submerged in water, would displace more water than a l
ump of gold of equal weight.
Archimedes ran to the king with his news. He then measured the displacement of the cr
own and a lump of gold of equal
weight and discovered that the crown displaced more water and was therefore not pur
e gold. The experiment
confirmed that the goldsmith had indeed attempted to deceive the king.
You’ve almost certainly noticed that your arms and legs are light
er when you’re underwater. This is because
the water helps to support your weight. Archimedes called this “buoyancy.” If t
wo objects have the same weight
but different volumes, the one with the higher volume will displ
ace more water, which means that it will have
greater buoyancy. This phenomenon became known as Archimedes’ principl
e. You’ve come across it already, in
your adventures with Pepper Mint.
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