Читать книгу Bicycling for Ladies. The Common Sense of Bicycling; with Hints as to the Art of Wheeling—Advice to Beginners—Dress—Care of the Bicycle—Mechanics—Training—Exercise, etc., etc онлайн

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The wheel being set in motion, power is applied to overcome inertia, and speed is increased by multiplying the number of the wheel’s revolutions; the application of the gyroscope principle assists materially, and the resistance of gravity is overcome in a degree while the wheels are rapidly revolving.

To set a bicycle in motion requires the expenditure of considerable power. A given rate of speed on the level may be maintained by a minimum expenditure of power. Bodies or masses set in motion maintain their velocity undiminished unless other forces intervene. The bicycle in motion is resisted on the level by air pressure and friction, on the roadway by friction, and by the incidental obstacles of the road. On an ascending plane, it must overcome the additional resistance of its own and its rider’s weight, which must be lifted constantly; on a descending plane, it must oppose a constantly lessening resistance. All this resistance and lack of resistance means a proportionate stress laid upon the bicycle, the wheels of which are all the while kept rapidly revolving, the large wheels moving much faster than the cranks and pedals.