29 SEP 2017 by ideonexus

 Roman Arithmetic

...basic Roman arithmetic is largely rather simple, even for those of us spoiled by Arabic notation. Addition is no sweat, because complex Roman numbers already use what math pros call additive notation, with numerals set beside one another to create a larger number. VI is just V plus I, after all. To add large numbers, simply pile all the letters together, arrange them in descending order, and there’s your sum. CLXVI plus CLXVI? CCLLXXVVII, or CCCXXXII. And one of the advantages of the Rom...
Folksonomies: math mathematics education
Folksonomies: math mathematics education
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13 OCT 2013 by ideonexus

 The Clock as the Mother of All Machines

PRECISELY because the clock did not start as a practical tool shaped for a single purpose, it was destined to be the mother of machines. The clock broke down the walls between kinds of knowledge, ingenuity, and skill, and clockmakers were the first consciously to apply the theories of mechanics and physics to the making of machines. Progress came from the collaboration of scientists—Galileo, Huygens, Hooke, and others—with craftsmen and mechanics. Since clocks were the first modern measur...
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It required a number of sciences, was based on multiple engineering developments, and contributed itself to science by allowing the measurement of time.

21 JUN 2012 by ideonexus

 Conception of Time

We never really see time. We see only clocks. If you say this object moves, what you really mean is that this object is here when the hand of your clock is here, and so on. We say we measure time with clocks, but we see only the hands of the clocks, not time itself. And the hands of a clock are a physical variable like any other. So in a sense we cheat because what we really observe are physical variables as a function of other physical variables, but we represent that as if everything is evo...
Folksonomies: time
Folksonomies: time
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We do not see time, we only see its effects.

17 MAY 2012 by ideonexus

 Benjamin Franklin on Daylight Savings Time

I say it is impossible that so sensible a people [citizens of Paris], under such circumstances, should have lived so long by the smoky, unwholesome, and enormously expensive light of candles, if they had really known that they might have had as much pure light of the sun for nothing.
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Noting that the people of Paris spend much money on candles when they could simply adjust their clocks to rise with the sun.

01 JAN 2012 by ideonexus

 A Clock Stopped at the Moment Feynman's Wife Died

Sometimes we can actually pin down the explanation of a weird coincidence. A great American scientist called Richard Feynman tragically lost his wife to cancer, and the clock in her room stopped at precisely the moment she died. Goose-pimples! But Dr Feynman was not a great scientist for nothing. He worked out the true explanation. The clock was faulty. If you picked it up and tilted it, it tended to stop. When Mrs Feynman died, the nurse needed to record tl the time for the official death ce...
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But he traced the phenomenon to a faulty mechanism in the clock that triggered when the nurse picked it up to record the time of death.