A Mechanical Text-book: Or, Introduction to the Study of Mechanics and EngineeringC. Griffin, 1873 - 312 من الصفحات |
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عبارات ومصطلحات مألوفة
A₁ acting angular velocity applied Article B₁ B₂ balance band beam belt C₁ called centre of gravity circular comparative motion components connected points cord couple coupling rod crank arm curve cylinder denote diameter direction of motion divided driving point energy epicycloids epitrochoids equal and opposite Equation exerted expressed factor of safety figure fluid frame friction given instant instantaneous axis intersect interval joint length line of action line of connection load machine magnitude moment of inertia moving pieces multiplied numbers of teeth oblique P₁ pair of points parallel forces perpendicular perpendicular distance piston pitch circle pitch surface polygon position pressure principles produced proportional pulleys r₁ r₂ radii radius ratio relatively represented resistance respectively resultant right angles rigid body rotating piece screw shafts shearing stress sliding piece straight line stress T₁ threads tion traversing v₁ velocity-ratio weight wheel
مقاطع مشهورة
الصفحة 221 - The i:ni. u u. . of a machine is a fraction expressing the ratio of the useful work to the whole work performed, which is equal to the energy expended. The limit to the efficiency of a machine is unity, denoting the efficiency of a perfect machine in which no work is lost. The object of improvements in machines is to bring their efficiency as near to unity as possible.
الصفحة 107 - The tendency of a couple is to turn the body to which it is applied in the plane of the couple — that is, the plane which contains the lines of action of the two forces. (The...
الصفحة 109 - Each of the three forces is equal and opposite to the resultant of the other two; and each pair of forces are equal and opposite to the components of the third. Hence this rule serves to resolve a given force into two parallel components acting in given lines in the same plane.
الصفحة 107 - ... the ratio of the mass of a given volume of the substance to the mass of an equal volume of water, in which case it is equal to the specific gravity.
الصفحة 229 - ... the friction of the water in the pumps and pipes, the friction of the plungers, pistons, valves, and mechanism, and the resistance of the air pump and other parts of the engine. For example, the useful work of a marine steam engine in a given time is the product of the resistance opposed by the water to the motion of the ship, into the distance through which she moves : the lost work is that performed in overcoming the resistance of the water to the motion of the propeller through it, the friction...
الصفحة 6 - B sin (A — B) = sin A cos B — cos A sin B cos (A + B) = cos A cos B — sin A sin B...
الصفحة 107 - If three forces acting on a particle keep it in equilibrium, each is proportional to the sine of the angle between the other two.
الصفحة 14 - To find the area of a trapezoid. RULE. Multiply half the sum of the two parallel sides "by the perpendicular distance between them : the product will be the area.
الصفحة 2 - ... figures in that number; that is to say, for numbers less than 10 and not less than 1, the index is 0; for numbers less than 100 and not less than 10, the index is 1 ; for numbers less than 1000, and not less than 100, the index is 2 ; and so on. The index of the common logarithm of a decimal fraction less than 1 is negative, and is one more than the number of noughts between the decimal point and the significant figures; and the negative sign is usually written above instead of before the index...
الصفحة 2 - Suppose a* =n, then x is called the logarithm of n to the böge a ; thus the logarithm of a number to a given base is the index of the power to which the base must be raised to be equal to the number. The- logarithm of n to the base a is written Iog0 n ; thus log„ii = a; expresses the same relation, as a* = n.