How to use Pendulum in a sentence
The pendulum has swung back.
The times were measured by pendulum clocks.
And then he walked away, his shoulders swaying like a pendulum with his stride.
His application of the pendulum to regulate the movement of clocks sprang from his experience of the need for an exact measure of time in observing the heavens.
For small earthquakes, in which the movement is rapid, the bob of a very long and heavy pendulum will practically comply with these conditions.Advertisement
A simple form of horizontal pendulum as shown in fig.
It is found that the motion of the galvanometer mirror faithfully records, except in a few special cases, the motion of the pendulum; the actual record is made on sensitized paper.
For his demonstration in 1851 of the diurnal motion of the earth by the rotation of the plane of oscillation of a freely suspended, long and heavy pendulum exhibited by him at the Pantheon in Paris, and again in the following year by means of his invention the gyroscope, he received the Copley medal of the Royal Society in 1855, and in the same year he was made physical assistant in the imperial observatory at Paris.
The pendulum has now swung too far, and we need to reconsider where the boundary should be drawn.
The determination of the true relation between the length of a pendulum and the time of its oscillation; the invention of the theory of evolutes; the discovery, hence ensuing, that the cycloid is its own evolute, and is strictly isochronous; the ingenious although practically inoperative idea of correcting the "circular error" of the pendulum by applying cycloidal cheeks to clocks - were all contained in this remarkable treatise.Advertisement
Nor is this its only association with science; for it was one of the spots chosen by Sir Edward Sabine for his series of pendulum experiments in 1823.
Instruments largely employed for this purpose in Italy are ordinary pendulum seismographs as in fig.
The more distant this is from the pendulum the greater is the magnification of the angular movements of the mirror.
If we wish to obtain mechanical registration from a horizontal pendulum of the above type, we may minimize the effect of the friction of the writing index - say a glass fibre touching the smoked surface of moderately smooth paper - by using a considerable weight and placing it near to the outer end of the boom.
This instrument was made with a pendulum weight of I loo kilos or over a ton; and with a modified construction the weight was increased to 17,000 kilos or nearly 19 tons, portability being obtained by replacing the solid pendulum of the smaller instrument by a shell which can be filled with barytes, a heavy mineral readily obtainable in most places.Advertisement
An air-damping apparatus is attached in order to annul the natural oscillations of the pendulum.
The Galitzin seismograph, devised by Prince Galitzin, is of the same type, but it essentially differs from the Milne instrument in having its pendulum dead-beat; this is brought about by an electromagnetic device.
Attached to the pendulum is a coil of fine wire which moves in the field of a pair of magnets.
The currents induced in the coil are led to a dead-beat D'Arsonval galvanometer having the same natural period of vibration as the pendulum.
On the voyage he noticed the retardation of the pendulum in approaching the equator; and during his stay on the island he observed, on the 7th of November 1677, a transit of Mercury, which suggested to him the important idea of employing similar phenomena for determining the sun's distance.Advertisement
It is a notable feature of the new movement, that except verbally, in a certain licence of nominalist expression, due to the swing of the pendulum away from the realist doctrine of universals, there is little that we can characterize as Empiricism.
The small oscillations of a simple pendulum in a vertical plane also come under equation (5).
This applies to the inverted pendulum, with u =g/l, but the equation (9) is then only approximate, and the solution therefore only serves to represent the initial stages of a motion in the neighborhood of the position of unstable equilibrium.
A simple mechanical, illustration is afforded by the pendulum.
In the case of the pendulum the tension of the string takes the place of the pressure of the curve.Advertisement
A pendulum is constructed with two parallel knife-edges as nearly as possible in the same plane with G, the position of one of them being adjustable.
If it could be arranged that the period of a small oscillation should be exactly the same about either edge, the two knifeedges would in general occupy the positions of conjugate centres of suspension and oscillation; and the distances between them would be the length 1 of the equivalent simple pendulum.
This solution has been discussed to some extent in 12, in connection with the forced oscillations of a pendulum.
C a A revolving pendulum is an essential part of most of the contrivances called governors, for regulating the speed of prime movers, for further particulars of which see STEAM
In these researches he skilfully took advantage of the well-known property of reciprocity between the centres of suspension and oscillation of an oscillating body, so as to determine experimentally the precise position of the centre of oscillation; the distance between these centres was then the length of the ideal simple pendulum having the same time of oscillation.Advertisement
And the machine is arranged to weigh goods up to 8 lb with the fixed weight only on the pendulum, and up to 16 lb with an additional weight which can be readily slipped on to the pendulum rod.
The same disk carries the index arm, which is rigidly fixed to it and indicates the weight and value of the goods, and also carries the pendulum, which is rigidly attached to it, and regulates the position of the index arm according to the position which it takes up and the leverage which it exerts when swayed out of the vertical position by the action of the lever of the lever machine.
The registration is effected by the fall of a heavy pendulum, caused by the percussion of each step. The pendulum is forced back to a horizontal position by a delicate spring, and with each stroke a fine-toothed ratchet-wheel connected with it is moved round a certain length.
A confused and unsatisfactory war in Afghanistan, troubles yet more unsatisfactory in South Africa, conspired with two or three years of commercial distress to invigorate "the swing of the pendulum" when he dissolved parliament in 1880.
He continued his scientific correspondence with unbroken interest and undiminished logical acumen; he thought out the application of the pendulum to the regulation of clockwork, which Huygens successfully realized fifteen years later; and he was engaged in dictating to his disciples, Viviani and Torricelli, his latest ideas on the theory of impact when he was seized with the slow fever which in two months brought him to the grave.Advertisement
Without the Earth 's rotation having ceased, the pendulum has been noted to stop.
We also have a range of rune sets, crystal ball sets, chakra sets, crystal ball cushions, pendulum sets.
According as it is too great or too small, the stroke of the pendulum is shortened or lengthened by a screw.
These suggestions took practical shape by a decree of the National Assembly in 1790 appointing a committee to consider the suitability of adopting either the length of the seconds pendulum, a fraction of the length of the equator or a fraction of the quadrant of the terrestrial meridian..
The experimental verification of this fact led him to the important discovery of the isochronism of the pendulum.Advertisement
My job is to make sure the pendulum never swings too far into the court of the Black God.
Surely the workers would be allowed an independent arbitration, or a pendulum system like they do in Japan.
There are two forces acting on the pendulum bob.
The pendulum's motion can be detected using an induction coil.
This could easily lead to a pendulum swing to a new irrationalism.Advertisement
In it hangs the lamp whose measured swing suggested to Galileo the pendulum.
The pendulum of rampant materialism has now swung too far, correspondingly to be rebuked by new forces of dissent.
The most accurate pedometer in our range uses solid state accelerometer technology instead of the traditional mechanical pendulum used in most other pedometers.
As a dowsing pendulum it is the perfect tool!
A prepared test piece, usually notched, is broken by a swinging pendulum.Advertisement
I had a pendulum with me so I asked Jane to sit at the table and hold the pendulum just above the surface.
We investigate an inverted pendulum on a cart subject to a delayed feedback control force which tries to balance the pendulum.
The simple pendulum consists of a weight hanging at the end of a string or wire.
The method is illustrated by two numerical examples, namely a single pendulum on a cart and a parametrically driven inverted double pendulum.
Waiting for the political pendulum to swing has not worked.
I do use a quartz crystal pendulum for this work.
The sudden, erratic swings of the pendulum during the 1990s were, therefore, the perfect prelude to the 2000 campaign.
Without the earth's rotation having ceased, the pendulum has been noted to stop.
It exhibits many of the characteristics of Church and brings a welcome pendulum swing back to the emphasis on the small unit of church.
Their parents had a tabletop " grandfather's clock "; in other words a clock with a pendulum.
The mutual distances of the intersecting wires he determined by counting, with the aid of a pendulum clock, the number of seconds required by an equatorial star to pass from web to web, while the telescope was adjusted so that the star ran parallel to the wires at right angles to those under investigation.
In Great Britain and America the complete vibration to and fro (swing both ways of a pendulum) is taken as the unit; elsewhere the vibration in one direction only (swing one way of the pendulum).
When at the limits of its swing, the pendulum is for an instant at rest, and all the energy of the oscillation is static or potential.
Such a pendulum can be set in vigorous vibration even by feeble puffs of air directed against it, provided these are administered exactly in time with the natural period of vibration of the pendulum.
But Lord Salisbury's retirement, Unionist divisions, the staleness of the ministry, and the accumulating opposition in the country to the Education Act of 1 9 02 and to the continued weight of taxation, together with the growth of the Labour movement, and the antagonism to the introduction of Chinese coolies (1904) into South Africa under conditions represented by Radical spokesmen as those of "slavery," made the political pendulum swing back.
The ellipsoid was the shape first worked out, by George Green, in his Research on the Vibration of a Pendulum in a Fluid Medium (2833); the extension to any other surface will form an important step in this subject.
Recent pendulum observations have shown that it is incorrect to assume a uniform density of 2.6 in the elevated part of the earth's crust, that on the contrary there are great local differences in density, the most important being a confirmation of Airy's discovery that there is a marked deficiency of mass under high mountains and a marked excess under the bed of the ocean.
In particular he carried out an extensive series of experiments in gunnery, embodying his results in his famous treatise on New Principles in Gunnery (1742), which contains a description of his ballistic pendulum (see Chronograph).
The Strassburg or Bosch seismograph differs from those just described in resembling the Milne instrument, it is a horizontal and not a vertical pendulum.
A simple example of the transformation of kinetic energy into potential energy, and vice versa, is afforded by the pendulum.
These oscillations of opinion arP frequent, if not universal, and it is only after more than one or two swings that the pendulum remains at the perpendicular.
But if the fork has, say, rather greater frequency, the hole in the wheel comes round at the end of the two seconds before the bead has quite come into position, and the two flashes appear gradually to move back in the opposite way to the pendulum.
Vicentini of Padua, will yield excellent diagrams of the gentle undulations of earthquakes which have originated at great distances, but for local disturbances, even if the bob of the pendulum acts as a steady point, the highly multiplied displacements are usually too great to be recorded.
An apparatus of great value in measuring slight changes in the vertical which have a bearing upon seismometrical observation is the Darwin bifilar pendulum.
In the Agamennone seismometrograph the pendulum is cheese-shaped, and weighs 500 kilos in one form and 2000 kilos, or over two tons, in the largest.
In the Wiechert astatic pendulum seismometer the stationary mass is also cheese-shaped, but it is supported by a conical extension from its base, which balances it on the floor of its case.
There is also an extension from the upper surface of the pendulum, in contact with a system of levers and rods attached to the case; an air-dampkig cylinder is fitted to annul the free vibrations of the pendulum.
A compound pendulum is a body of any form which is free to rotate about a fixed horizontal axis, the only extraneous force (other than the pressures of the axis) being that of gravity.
This coincides with the equation of motion of a simple pendulum [E 13 (15)] of length 1, provided 1= hf/h.
If we produce OG to P, making OP =1, the point P is called the centre of oscillation; the bob of a simple pendulum of length OP suspended from 0 will keep step with the motion of P, if properly started.
The formula (13) may be easily verified in the case of the compound pendulum, or of the solid rolling down an incline.
As regards the most general motion of a spherical pendulum, it is obvious that a particle moving under gravity on a smooth sphere cannot pass through the highest or lowest point unless it describes a vertical circle.
This gives (in essentials) the theory of the gyroscopic pendulum.
As an example of the method of determination of the normal modes we may take the double pendulum.
This combination is Z called a revolving, centrifugal, or conical pendulum.
If the rod of a revolving pendulum be jointed, as in fig.
His enquiries into evolutes enabled him to prove that the evolute of a cycloid was an equal cycloid, and by utilizing this property he constructed the isochronal pendulum generally known as the cycloidal pendulum.
This lever is so counterbalanced that when there is no weight in the pan the pendulum is vertical, and the index arm should then stand at zero.
An example of an oval table 1907 saw the brief reign of the " pendulum cannon " in English billiards.
Instructions are given on how to construct a pendulum clock, and readers ' questions are answered.
The glazed trunk door reveals the swing of the pendulum and the gradual drop of the weights.
The game now swung like a pendulum from end to end, and the atmosphere was electric.
Their parents had a tabletop " grandfather 's clock "; in other words a clock with a pendulum.
R. anthopogon, flowers sulphur-yellow; R. glaucum, flowers dull rose-purple; and R. pendulum, flowers white, are small-leaved dwarf shrubs, chiefly of botanical interest.
From pendulum to spots, you can mix and match a variety of heads to design a truly unique look.
If it swings back and forth like a pendulum, the baby is a boy.
This is a sign that constantly swings like a pendulum from one side to the other.
At this point you may be asking yourself why the pendulum has swung so drastically in recent years toward the side of boxers?
Such a system is called "conservative," and is well illustrated by the swinging pendulum above referred to.
Believing that the pendulum had overshot its swing from conventional classicality towards pictorial realism, he turned from the " fleshy " school towards the Greek, while realizing the artistic necessity for modern feeling.
Let us suppose that he notes the positions of two of these next to each other in the beat of the pendulum one way.
There is a lot of detail in the clock surround and the clocks are pendulum driven.
I got a part on Pendulum and thought this was the best career ever because I could eat (that’s a joke, seriously!).
In the north the pendulum swung back once more and the French reoccupied Milan in April, causing the downfall of the Sforzas, much to Alexander's gratification.
In a refined form this method is often employed for measuring the intensity of a magnetic field at a given place, just as the intensity of gravity at different parts of the earth is deduced from observations of the rate at which a pendulum of known length vibrates.
By the end of the century, however, owing to a great extent to the publication of the essays of Malthus, the pendulum had swung far in the opposite direction, it was thought desirable to possess the means of judging from time to time the relations between an increasing population and the means of subsistence.
There was one opening in its disk, and through this was viewed the pendulum of a clock beating seconds.
On the pendulum was fixed an illuminated silver bead which appeared as a bright point of light when seen for an instant.
If the fork makes exactly 32 vibrations and the wheel 8 revolutions in one pendulum beat, then the positions will be fixed, and every two seconds, the time of a complete pendulum vibration, he will see the two positions looked at flash out in succession at an interval of a second.
Then the first flash in the new position is viewed by the 8Nth passage of the opening, and the second flash in the original position of the first is viewed when the pendulum has made exactly N beats and by the (8 N + i)th passage of the hole.
Below this pendulum let there be placed another coil through which passes the current to be measured; then when currents pass through these coils the pendulum of the second clock will be either accelerated or retarded relatively to the other clock, since the action of gravity is supplemented by that of an electric attraction or repulsion between the coils.
He clearly perceived the significant analogy between terrestrial gravity and the force exerted in the solar system, and by the ingenious device of a circular pendulum illustrated the composite character of the planetary movements.
He attained correct views as to the character of centrifugal force in connexion with Galileo's theory; and, when the fact of the variation of gravity (Galileo's acceleration) in different latitudes first became known from the results of pendulum experiments, he at once perceived the possibility of connecting such a variation with the fact of the earth's diurnal rotation relatively to the stars.
But Huygens's most important contribution to the subject was his investigation, published in 1673, of the motion of a rigid pendulum of any form.
Foucault's pendulum is another example of motion relative to the earth which exhibits the fact that the earth is not a Newtonian base.
The use of the pendulum clock in its present form appears to date from the construction of such a clock by Huygens in 16J7.
This type of apparatus has been replaced in Japan by what are called duplex pendulum seismographs.
The change was made because it frequently happened that in consequence of the movement of the ground agreeing with the period of the pendulum, the latter no longer acted as a steady point, but was caused to swing, and the record became little better than that given by a seismoscope.
In the new position b would tend to follow the direction of its point of support, whilst c would tend to fall in the opposite direction, and the bob of one pendulum would exercise a restraint upon the motion of the other.
In this way, by coupling together an ordinary pendulum about 3 ft.
Chladni's experiment of strewing a vibrating bell with flour, investigated the nature of sound and the function of the air in respiration and combustion, and originated the idea of using the pendulum as a measure of gravity.
During Nansen's expedition on the " Fram " in 1894-1895, Scott Hansen made observations with a Sterneck's half-seconds pendulum on the ice where the sea was more than 1600 fathoms deep and found only an insignificant deviation from the number of swings corresponding to a normal ellipsoid.
If the bob of the pendulum is iron, and if a coil is placed just below the centre of swing, then, if a current passes through the coil, while and only while the bob is moving towards it, the vibration is maintained.
As was naturally to be expected, the pendulum swung to the other extreme, and in a more critical age the existence of Arthur was roundly denied.
He has therefore lost sight of the truths that bodies are triply extended, mutually impenetrable substances, and by this force causes which reduce one another to a joint mass with a common velocity on collision, as for instance in the ballistic pendulum; that these forces are the ones we best understand; and that they are reciprocal causes of the common velocity of their joint mass, whatever happens afterwards.
He had, however, some years before, when he was a medical student, noticed the apparent regularity of successive swings of a pendulum, and devised an instrument for measuring, by means of a pendulum, such short periods of time as sufficed for testing the pulse of a patient.
For example, if the falling body s is attached by a thread to the pendulum of a timepiece, it may be used to stop it and indicate the approximate time at which the tremor occurred.
If a style projecting from this pendulum rests upon say the smoked surface of a glass plate fixed to the ground, the vibratory motion of the ground will be recorded on the glass plate as a set of superimposed vibrations.
Here the style s of the pendulum rests in slots in the short arms of two writing levers pivoted at o and o'.
At the beginning of 1680 he presented a paper to the Royal Society, De nova temporis dimetiendi ratione et accurata horologiorum .constructione, in which he attempted to deprive Huygens of the honour of applying the pendulum to the measurement of time.
In 1826 the idea occurred to him of attacking this problem by means of pendulum experiments at the top and bottom of a deep mine.
In order to understand the sharp swing of the political pendulum back from republicanism to autocracy which took place at Brumaire, it is needful to remember that the virtual failure of the Egyptian Expedition was then unknown.
Thus if a pendulum always receives a slight impulse in the direction of motion just about the lowest point, this is equivalent to an increase of the restoring force if received before passage through the lowest point, and to a decrease if received after that passage, and in either case it tends to maintain the swing.
By the use of a permanent magnet instead of a shunt coil as the bob of one pendulum, the meter can be made up as an ampere-hour meter.