First Lessons in Theoretical Mechanics |
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absolute units accelerative effect angle of friction angular velocity axis axle body moves centre of gravity centrifugal force coefficient of friction compression consequently couple cubic cylinder denote density described determined diameter distance draw effect of gravity elastic energy equation equilibrium exerted expended fall feet and seconds foot-pounds force of gravity forces acting given gravitation units Hence horizontal inclined inertia instant last article last question length machine mass mercury modulus moment of inertia momentum motion mutual action opposite directions oscillation parallel forces parallelogram pendulum piston plane position principle of moments radius radius of gyration reaction resistance respectively rest resultant right angles round screw specific gravity square inch student suppose surface tensile stress thread three forces triangle turn uniform acceleration units act vertical line vessel weight
Popular passages
Page 187 - Whatever draws or presses another is as much drawn or pressed by that other. If you press a stone with your finger, the finger is also pressed by the stone. If a horse draws a stone tied to a rope, the horse (if I may so say) will be equally drawn back towards the stone...
Page 186 - Every body continues in its state of rest or of uniform motion in a straight line, except in so far as it may be compelled by impressed forces to change that state.
Page 187 - Change of momentum is proportional to the impressed moving force, and takes place along the straight line in which that force is impressed.
Page 187 - ... and it will impede the progress of the one as much as it advances the progress of the other. If a body strike on another body, and by its force change the momentum of the latter body in any way whatever, its own momentum will in turn undergo an equal change in a contrary direction from the force of the latter body, in consequence of the equality of the mutual pressure.
Page 110 - If the wagon goes out fourteen times, each man has to fill seven wagons in the course of the day. Each wagon contains two and a quarter cubic yards. The result is, that each man has to lift nearly twenty tons weight of earth on a shovel over his head into a wagon. The height of the lifting is about six feet. This is taking it at fourteen sets a day ; but the navvies sometimes contrive to get through sixteen sets, and there are some men who will accomplish that astonishing quantity of work by three...
Page 187 - If any one presses a stone with his finger, the finger is also pressed by the stone. If a horse is drawing a stone tied to a rope, the horse is (so to speak) equally drawn back towards the stone; for the rope...
Page 50 - ... the sum of the moments of the forces which tend to turn the body in one direction must be equal to the sum of the moments of those which tend to turn it in the opposite direction about the same axis.
Page 109 - Take, for example, the following extract from the interesting life of Mr. Brassey : — "The labour which a navvy performs exceeds in severity almost any other description of work. A full day's work consists of fourteen sets a day ; a set is a number of wagons — in fact a train.
Page 92 - Every engineer knows that the work done by a force has to be measured by multiplying together the force and the distance through which its point of application moves forward.
Page 3 - The ratio of the mass of any quantity of a substance to the mass of an equal volume of some standard substance. In the case of solids and liquids the latter is chosen as water at 4° C.