Word Finder - amplitude

definition

The measure of something's size, especially in terms of width or breadth; largeness, magnitude.

definition

The maximum absolute value of the vertical component of a curve or function, especially one that is periodic.

definition

The maximum absolute value of some quantity that varies.

definition

The arc of the horizon between the true east or west point and the center of the sun, or a star, at its rising or setting. At the rising, the amplitude is eastern or ortive: at the setting, it is western, occiduous, or occasive. It is also northern or southern, when north or south of the equator.

definition

The arc of the horizon between the true east or west point and the foot of the vertical circle passing through any star or object.

definition

The horizontal line which measures the distance to which a projectile is thrown; the range.

In both cases the amplitude of the oscillations decreases more or less rapidly.

Thus Mach found an amplitude 0 2 cm.

The 12-hour term is much less variable, especially as regards its phase angle; its amplitude shows distinct maxima near the equinoxes.

The maximum velocity of a particle in the wave-train is the amplitude of dy/dt.

Each section then vibrates, and its amplitude goes through all its values in time given by 21rUT/A =2r, or T =A/U, and the frequency is U/A.

Methods of measuring the amplitude in sound waves in air have been devised and will be described later.

Further, the same harmonics with the same amplitude will always be present.

The result was an amplitude of 1.27 X 107 cm.

The amplitude of the fork was observed when the sound just ceased to be audible at 27.4 metres away, and the rate of energy emission from the resonator was calculated to be 42 .

This rate of loss for each amplitude was determined (i) when the fork was vibrating alone, and (2) when a resonator was placed with its mouth under the free ends of the fork.

If th' maximum pressure change is determined, the amplitude is given by equation (20), viz.

The amplitude in the pipe was certainly much greater than in the issuing waves.

When the plate vibrated the mirror was vibrated about the fixed edge, and the image of a reflected slit was broadened out into a band, the broadening giving the amplitude of vibration of the plate.

For minimum audible sounds Wien found a somewhat smaller value of the amplitude than Rayleigh.

The effects due to each of these rings are equal in amplitude and of phase ranging uniformly over half a complete period.

The amplitude is thus subject to fluctuations, which increase as the shadow is approached.

Half the total excursion is called the amplitude.

Now the amplitude evidently corresponds to the loudness, and the length of period corresponds to the pitch or frequency.

They are connected with the ocean by narrow straits, the salinity of the water contained in them differs in a marked degree from that of the ocean, and the tidal waves are of small amplitude.

We may say here that the energy or the intensity of the sound of given wave-length is proportional to the square of the amplitude.

Another important result of the investigation was that the phase of vibration of the fork was not altered by bowing it, the amplitude alone changing.

If we measure the time from an instant at which the two are in the same phase the resultant disturbance is y=a sin i t+a sin 27rn2t =2a cos ir(n i - n 2)t sin ir(nl-t-n2)t, which may be regarded as a harmonic disturbance of frequency (ni+n2)/2 but with amplitude 2a cos 7r(n i - n 2)t slowly varying with the time.

The rate of diminution of amplitude expressed by the coefficient a in the index of the exponential is here greater than the coefficient b expressing the retardation of phase by a small term depending on the emissivity h.

Now if a be the amplitude expressed in millimetres, and t the period expressed in seconds, then the maximum velocity of an earth particle as it vibrates to and fro equals 27ra/t, whilst the maximum acceleration equals 4,r 2 0 2.

Neither of them seemed to recognize anything as important except pitch and amplitude, and Reis thought the amplitude was to some extent obtained by the varying length of contact in the transmitting instrument.

In mechanics, the amplitude of a wave is the maximum ordinate.

The maximum particle velocity is 21rna (where n is the frequency and a the amplitude), or 27raU/X.

The maximum height of the curve HM =a is the amplitude.

In the other, the waves produce a measurable effect on a vibrating system of the same frequency, and the amplitude in the waves can be deduced.

The amplitude found by the other observers was of the same order.

The formation of beats may be illustrated by considering the disturbance at any point due to two trains of waves of equal amplitude a and of nearly equal frequencies n, n2.

Taking the squares of the amplitude to represent the intensity or loudness of the sound which would be heard by an ear at the point, this is 4a 2 cos t ir(ni - n2)t =2a 2 {1 -cos 27r(n l - n2)t}, a value which ranges between o and 4a 2 with frequency .n1 - n2.

If, instead of considering one point in a succession of instants, we consider a succession of points along the line of propagation at the same instant, we evidently have waves of amplitude varying from 2a down to o, and then up to 2a again in distance U/(ni - n2).

Formerly it was generally supposed that the Tartini tone was due to the beats themselves, that the mere variation in the amplitude was equivalent, as far as the ear is concerned, to a superposition on the two original tones of a smooth sine displacement of the same periodicity as that variation.

Let us suppose that with constant excess of pressure, p, in the wind-chest, the amplitude produced is proportional to the pressure, so that the two tones issuing may be represented by pa sin 27-nit and pb sin 21rn 2 t.

Moreover, a tendency to amplitude of language may be noticed here and there in some of the more concise narratives.

Lord Kelvin assumed as a superior limit of k, the ratio of amplitude to wave-length, the value io 2, which is a very safe limit.

It thus appears that if the amplitude of vibration could be as much as 1 o_2 of the wave-length, the aether would be an excessively rare medium with very slight elasticity; and yet it would be capable of transmitting the supply of solar energy on which all terrestrial activity depends.

In creased length necessitated an increase in the diameter of the main tube to limit the amplitude of the vibrations caused by being pushed through the water.

To illustrate the main features of the calculation, we may suppose that the surface is subject to a simple-harmonic cycle of temperature variation, so that the temperature at any time t is given by an equation of the form 0 - 0 0 = Asin 27rnt= A sin 27rt/T, (5) where 0 0 is the mean temperature of the surface, A the amplitude of the cycle, n the frequency, and T the period.

In this simple case the temperature cycle at a depth x is a precisely similar curve of the same period, but with the amplitude reduced in the proportion rn ', and the phase retarded by the fraction mx/27r of a cycle.

The dotted boundary curves have the equation 0 =omx, and show the rate of diminution of the amplitude of the temperature oscillation with depth in the metal.

Although by compounding corresponding portions of the diagrams given by instruments of this type, it is possible to determine the range and direction of the movement of which they are the resolved parts, their chief value is that they enable us to measure with ease the extent of any vibration, half of which is called its amplitude, and the time taken to make any complete back-and-forth movement, or its period.

The numbers correspond to an amplitude of 10 centimetres and a period of two seconds.

This may be described as a simple harmonic oscillation whose amplitude diminishes asymptotically to zero according to the law ehlr.

If the friction be comparatively slight the amplitude is greatest when the imposed period coincides with the free period, being then equal to f/kei, and therefore very great compnred with that due to a slowly varying force of the same average intensity.

The abnormal amplitude is greater, and is restricted to a narrower range of frequency, the smaller the friction.

The amplitudes of oscilla Ia tion of the various particles have definite ratios to one another, and the phases are in agreement, the absolute amplitude (depending on C) and the phase-constant () being alone arbitrary.

If the friction be small the amplitude becomes relatively very great if the imposed period approximate to a free period.

The amplitude of this part of his attire enables the Persian to sit without discomfort on his heels; chairs are only used by the rich, great or Europeanized.