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"The use of force alone is but temporary. It may subdue for a moment; but it does not remove the necessity of subduing again; and a nation is not governed, which is perpetually to be conquered."
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ForceWhen we swing a stone, attached to a , around our head, we are conscio — Force
"When we swing a stone, attached to a , around our head, we are conscious of a pull on the string, the stone by Newtons first and third law of motion tends to preserve the direction of its motion at any instant, and we are compelled, in order that the stone shall move in a circle, to exert a on the string. The reaction to this pull or tension is what is often called .The tension on the string is the . It will be seen that the centrifugal force is merely the tendency of the stone to continue in its line of motion, away from the hand, and is the reaction to the centripetal force."
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Force
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In physics, a force is an action that can cause an object to change its velocity or its shape, or to resist other forces, or to cause changes of pressure in a fluid. In mechanics, force makes ideas like pushing or pulling mathematically precise. Because the magnitude and direction of a force are both important, force is a vector quantity. The SI unit of force is the newton (N), and force is often
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"The laws of motion of visible and tangible, or molar, matter had been worked out to a great degree of refinement and embodied in the branches of science known as Mechanics, Hydrostatics, and Pneumatics. These laws had been shown to hold good... throughout the universe on the assumption that all such masses of matter possessed inertia and were susceptible of acquiring motion, in two ways, firstly by impact, or impulse from without; and, secondly, by the operation of certain hypothetical causes of motion termed forces, which were usually supposed to be resident in the particles of the masses themselves, and to operate at a distance, in such a way as to tend to draw any two such masses together, or to separate them more widely."
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"There are many changes in what concepts are important when we go from classical to quantum mechanics. ... In particular, the force concept gradually fades away, while the concepts of energy and momentum become of paramount importance. You remember that instead of particle motions, one deals with probability amplitudes which vary in space and time. In these amplitudes there are wavelengths related to momenta, and frequencies related to energies. The momenta and energies, which determine the phases of wave functions, are therefore the important quantities in quantum mechanics. Instead of forces, we deal with the way interactions change the wavelength of the waves. The idea of a force becomes quite secondary—if it is there at all. When people talk about nuclear forces, for example, what they usually analyze and work with are the energies of interaction of two nucleons, and not the force between them. Nobody ever differentiates the energy to find out what the force looks like."
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ForceQuote
"The wish to hurt, the momentary intoxication with pain, is the loophole through which the pervert climbs into the minds of ordinary men."
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ForceQuote
"Violence … is the last refuge of the incompetent."
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"I have always been fond of the West African proverb "Speak softly and carry a big stick; you will go far."
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