Shapes & Numbers
in
Stone & Ice
iMATHS
STONEHENGE at around 2500BC
2 types of stone:
●● Huge 'sarsens'; an incredible 25 – 40 tons
and towering up to 6.7 metres above
ground (with an estimated 2.3m beneath!)
●●
80 or so 'bluestones'; although smaller,
they still weigh 3 – 4 tons each and had
somehow been transported nearly 200 miles
from Wales!
2 entrances; 1 facing South and 1 North-East.
1 smaller inner circle of bluestones.
1 horseshoe-shape of 19 bluestones, probably
used to track an 18.61-year moon eclipse cycle.
15 hard-sandstone sarsens made into 5 massive
'trilithons'.
A trilithon is constructed by 3 (tri) stones (lithos),
with 2 stones upright and the 3rd stone across
the top. It reminds us at FUSE of the Pi symbol, Π.
30 upright sarsen stones (of which 17 still
stand today) with 30 lintels on top,
linked to form an outer continuous circle.
SNOWFLAKES
6 snowflake shapes are recognised by the
Royal Meteorological Society: star; needle;
flat plate; column; capped column; and
intricate, lacy dendrites.
A recent study identified 121 sub-types of
'solid precipitations'; things like snowflakes,
hailstones – even a frozen hydrometeor
particle! When grouped into their 39
categories, 35 are snow crystals or flakes.
Cloud temperature must be below 0° Celsius
(32° Fahrenheit) to form ice crystals. The exact
temperature and moisture content build the
shape of each snowflake. Also, dirt can affect
both crystals and the snowflake's flight path
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-but if a falling flake spins evenly, you can be
pretty sure it's symmetrical!
The average snowflake falls at a top speed of
1.7 metres per second.
Mathematicians generally agree with the phrase
that “2 snowflakes are never alike”. However
the Guinness World Records celebrate Nancy
Knight, an American scientist, who in 1988
found 2 identical examples while studying snow
crystals from a storm in Wisconsin!
FUSE
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