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


When you're standing on a fixed platform station and sweeps past her Express train, then jump in the car on the move, of course, surprising. But imagine that the platform beneath you, too, moves with such speed and in the same direction as the train. How hard will you then get in the car?

Not at all: you will enter as calmly as if the car was standing still. Once you and the train are moving in the same direction with the same speed, relative to you, the train is at peace. However, his wheels are spinning, but you will feel that they turn on the spot. Strictly speaking, all those things that we usually consider a fixed - for example, the train standing at the station - move with us around the axis of the globe and around the Sun; but practically we can consider this movement as it does not prevent us.

Therefore, it is quite conceivable to arrange it so that the train passing stations, accept and dropped off passengers at full speed without stopping. Devices of this kind often hosts exhibitions, to give the public the ability to quickly and easily explore their attractions scattered over a wide area. The extreme points of the exhibition space, like an endless tape, connect the Railways; passengers may at any time and in any place to enter the cars and leave them at full speed trains.

It is a curious device shown in the accompanying drawings. The first figure by the letters a and b marked at the station. At each station is placed round the stationary Playground, surrounded by a large rotating annular disk. Around the rotating discs of both stations bypasses the rope to which are attached the cars.

Diagram of the device of non-stop railway between the stations a and B.
The station device is shown in the following figure.

Now watch what happens when the disk rotates. Cars running around discs with such speed with which revolve their outer edges; therefore, passengers without the slightest danger can switch between drives in cars or, on the contrary, to leave the train. Coming out of the car, the passenger is on a rotating disk to the center of the circle until you reach the stationary platform; and to move with the inner edge of the rolling disk on a stationary platform is already easy, as here, with a small radius of a circle is quite small and peripheral speed. [It is easy to understand that the point of the inner edge moving much slower than the point of the outer edge, as at the same time describe a much smaller circular path.] Reaching the inner stationary platform, the passenger can only move along the bridge to the ground outside the railway.

The station non-stop Railways.

The lack of frequent stops and gives a great deal of time and energy. In urban trams, for example, most of the time and almost two-thirds of all energy is spent on gradual acceleration of the movement when the departure from the station and deceleration when stopping. [The loss of energy on braking can be avoided if the braking switch the motors of the car so that they worked as a Dynamo-machine, returning the current in the network. In Charlottenburg (a suburb of Berlin) thanks to the energy consumption for the trams had been cut by 30%. This technique is widespread on the electrified route Vladivostok - Moscow. (Approx. edit)]

On railway stations could be dispensed with without moving platforms to take and drop off passengers at full speed trains. Imagine that by ordinary fixed station sweeps Express train; we want it, without stopping, took new passengers. Let these passengers will take yet another train standing on an alternate parallel path, and let this train will begin to move forward, developing the same speed as courier. When both trains will be there, they will be fixed one relative to another: it is enough to throw a walkway that would connect the cars of both trains, and passengers auxiliary trains will be able to go to the courier. Stopping at stations shall be, as you can see, excessive.

Entertaining physics J. Perelman


System Orphus


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