Sec. 11. Force and Motion
Sir Isaac Newton’s first law of motion is written in these words:
“Every body continues in its state of rest, or of uniform motion in a straight line, except in so far as it is compelled, by force, to change that state.”—(Encyc. Brit. (9 ed.) 15, p. 676, “Mechanics.”)
“Energy may be defined,” says the Britannica, “as the power of doing work, or of overcoming resistance. A bent spring possesses energy, for it is capable of doing work in returning to its natural form; a charge of gun powder possesses energy for it is capable of doing work in exploding; a Leyden jar, charged with electricity possesses energy, for it is capable of doing work in being discharged.”—(Encyc. Brit. (9 ed.) 8, pp. 205-206, “Energy.”)
“Force is that which affects the motion of matter.”—(Encyc. Brit. (9 ed.) 7, p. 581, “Dynamics.”)
“The conclusion, which appears inevitable,” it says on another page, “is that whatever matter may be the other reality in the physical universe, energy, which is never found unassociated with matter, depends, in all its widely varied forms upon motion of matter.” (Encyc. Brit. (9 ed.) 15, p. 748, “Mechanics.”)
The sense of the above quotation is this: There are two realities in the physical universe: (1) matter, whatever it may be; (2) energy, which is always associated with matter. Energy “depends, in all its varied forms, upon motion of matter.” For example, let us suppose that we have three balls, designated as A, B, C, resting on a table in a straight line, one inch apart. Suppose that I strike A and drive it against B, that B strikes and moves C. In this case my arm moves and generates energy or force, which moves A against B, and B against C. The motion of my arm is the force which moves A; the motion of A is the force which moves B, and the motion of B is the force which moves C. Thus, we have demonstrated that energy or force generates motion; and that motions produces force; that is, that each is convertible into the other.
“Motion” is defined as “change of place; transition from one point or position in space to another; continuous variation of position.” (Cent. Dic. 5, p. 3872.)
Every human being begins life as a fertilized ovum, which is about as large as one-sixth of a pin’s head. At birth, an infant weighs from five to nine pounds, the average weight being six and one-half pounds. (New International Encyc. 7, p. 775.) It is then millions of times larger than a fertilized ovum. In other words: millions of atoms have been selected, assembled, chemically combined and mechanically arranged and grouped in such a manner as to form the body of a living infant, which is a complete miniature model of the body of a man or woman.