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J. Perelman
"Entertaining physics". Book 2.
Chapter 1. The basic laws of mechanics


On the principle of relativity of motion based and other device used so far only for exhibitions: the so-called "moving sidewalks". They were first implemented at the exhibition in Chicago in 1893, and then at the Paris world exhibition in 1900, Here is a drawing of such a device.

The moving sidewalks.

You see five closed lanes-sidewalks, moving through a special mechanism, one inside the other with different speeds.

The most extreme band is going very slowly - just 5 miles per hour; this is an ordinary walking pace, and to take this slowly creeping strip easily. Beside her, inside, running the second strip, at a speed of 10 km per hour. Jump on it right with a fixed street would be dangerous, but go at it with the first strip is worthless. Indeed: with regard to this first page, crawling at a speed of 5 km, the second, traveling at a speed of 10 km per hour, makes a total of only 5 km per hour; hence, to move from the first to the second is just as easy as to go from the ground to the first. The third band is moving with a speed of 15 km per hour, but go at it with the second strip, of course, easy. Just as easily go with the third strip to the next, fourth, running with a speed of 20 km/hour, and, finally, with her fifth rushing at the speed of 25 km per hour. This fifth band delivers passengers to the point that he needs; hence, consistently moving back from the lanes, he landed on the fixed land.

Entertaining physics J. Perelman


System Orphus


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