Physically Powered Motor
Some motors are powered by potential or kinetic energy, for example some funiculars, gravity plane and ropeway conveyors have used the energy from moving water or rocks, and some clocks have a weight that falls under gravity. Other forms of potential energy include compressed gases (such as pneumatic motors), springs (clockwork motors) and elastic bands.
Historic military siege engines included large catapults, trebuchets, and (to some extent) battering rams were powered by potential energy.
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Famous quotes containing the words physically and/or motor:
“I have witnessed, and greatly enjoyed, the first act of everything which Wagner created, but the effect on me has always been so powerful that one act was quite sufficient; whenever I have witnessed two acts I have gone away physically exhausted; and whenever I have ventured an entire opera the result has been the next thing to suicide.”
—Mark Twain [Samuel Langhorne Clemens] (1835–1910)
“We disparage reason.
But all the time it’s what we’re most concerned with.
There’s will as motor and there’s will as brakes.
Reason is, I suppose, the steering gear.”
—Robert Frost (1874–1963)