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J. Perelman
"Entertaining physics". Book 1.
Chapter 1. Speed. The addition of movements

A THOUSANDTH OF A SECOND

For us, accustomed to measure time on their human yardstick, a thousandth of a second is equivalent to zero. Such intervals have only recently began to meet in our practice. When the time was determined by the height of the Sun or the length of the shadow, then there could be no question of accuracy, even to the minute (Fig. 3); the people believed minute too insignificant value to be worth its measure. Ancient man lived such a leisurely life that his hours - sun, water, sand - no special marks for minutes


Define the time of day by the position of the Sun in the sky (left) and along the length of the shadow (right).


Water clock. used in the ancient world.


Vintage pocket watch.

What can be done in a thousandth of a second? Very much! The train, however, can move during this period of time only three centimeters, the sound is already at 33 cm, the plane - about half a meter; the globe will be held in its motion around the Sun in a fraction of a second to 30 m, and the light - 300 km

Small creatures that surround us, if they could talk, probably would not have considered it a thousandth of a second for a small period of time. For insects, for example, this value is quite noticeable. Komar for one second makes 500-600 full of flapping wings; means, in a thousandth of a second, he manages to raise them or lower.

People unable to move their members as quickly as the insect. The fastest we blink of an eye, blink of an eye”, or “MiG”in the original sense of these words. It is done so quickly that we do not notice even the temporary Eclipse of the field of our vision. Few, however, know that this movement is synonymous with unimaginable speed flows in essence quite slowly, if measured thousandths of a second. Full “moment” lasts as found accurate measurements, the average 2/5 seconds, i.e., 400 thousandths. It breaks down into the following phases: the lowering of the century (75 - 90 thousandths of a second), the state of immobility omitted century (130 - 170 mils) and picking it up (about 170 thousand). As you can see, one “moment” in the literal sense of the word - the span is quite substantial, during which eye eyelid even manages to relax a bit. And if we could separately to perceive impressions, lasting a thousandth of a second, we would catch “in a jiffy” two smooth motion eye century, separated by a period of rest.

With this device, our nervous system, we would see the world around us is transformed beyond recognition. The description of those strange paintings, which would then before our eyes, gave English writer wells in the story “New accelerator”. The heroes of the story drank a fantastic medicine that acts on the nervous system so that it makes sense organs susceptible to separate the perception of fast phenomena.

Here are a few examples from the story:

“ - Have you seen so far that the curtain was attached to the window sort of way?

I looked at the curtain and saw that it was as if frozen, and that the corner as she bent from wind, and left.

Is not never seen, " I said. "That's strange!

- And this? he said and opened the fingers holding the glass.

I expected that the glass will break, but he didn't even move, he hung in the air motionless.

"Of course, you know, " said Gibberne that the falling object falls in the first second of 5 m And a glass runs now these 5 m, but, you know, not even one hundredth of a second. [It should be borne in mind, moreover, that in the first hundredth of a share of the first second of its fall, the body is not the hundredth part of 5 m and 10000-Yu (according to the formula S = gt 2 /2, i.e. half-millimetre, and in the first thousandth of a second is only 1/200 mm] This can give you a notion of the power of my “accelerator”.

The glass slowly descended. Gibber ran his hand around the glass, above him and below him...

I looked out the window. Some cyclist, frozen in one place, with a frozen cloud of dust behind, caught up with some sort of cart, which also did not move a single inch.

... Our attention was attracted by the omnibus, absolutely petrified. The tip of the wheels, horse legs, the end of the whip and the lower jaw Kucera (he just started to yawn) - all this, albeit slowly, but moving; the rest in this clumsy crew completely frozen. Sitting there people were like statues.

...A man stood just at the moment when he made superhuman efforts to lay down in the wind the newspaper. But for us this wind did not exist.

...All that being said, thought, done by me with the time, as “accelerator” into my body, it was only a blink of an eye to other people, and for the whole universe”.

Likely readers will be interested to know, what is the least amount of time, measurable by means of modern science? At the beginning of this century it was $ 10000-th fraction of a second; now a physicist in his laboratory is capable of measuring 100000000000-th fraction of a second. This period about the same time less than a second, how many times a second is less than 3000 years!

Entertaining physics J. Perelman

 




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