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Thoughts for the pessimists
What makes your brain tick?
According to researchers, any part of your body, if you don't use it you lose
it, and particularly your brain, the more you use it the more brainy you
become.
Do You Know Why?
A cheap quartz watch is more accurate than my Rolex watch:
Through what's called the piezo-electric effect. If you squeeze certain types of
crystal, including quartz, they generate an electric field (that's also how
those kitchen gas-lighters create their spark).
The same effect also works in reverse: apply an electric field to quartz, and it
will change shape.
If you apply an alternating voltage fast enough, you can
persuade a suitably-cut quartz crystal to vibrate at four different 'natural
frequencies' of anything from 32,768 to 4,100,000 times per second.
In a quartz watch or clock, these vibrations form the 'tick-tock' signals needed
to mark out time.
Count 32,768 of them and you've got a second
(by comparison,
mechanical clocks manage no more than around 5 'tick-tocks' a second).
The faster the vibration, the more accurate the time-keeping:
☺ a cheap quartz
watch will easily manage to keep time to within one second a month, and
☺ a
precise quartz clock can keep time to around 1 second a decade.
Mantra: ‘You can't cure brain death but you can prevent
it.
What's the moral in these stories?
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