Galilean Relativity

2018 ◽  
Author(s):  
David M. Wittman
Keyword(s):  
Inertial Frame ◽  
Vertical Component ◽  
Horizontal Component ◽  
The Other ◽  
One Dimension ◽  
Everyday Experience ◽  
Low Speed ◽  
Principle Of Relativity ◽  
Galilean Relativity ◽  
Laws Of Motion

Galilean relativity is a useful description of nature at low speed. Galileo found that the vertical component of a projectile’s velocity evolves independently of its horizontal component. In a frame that moves horizontally along with the projectile, for example, the projectile appears to go straight up and down exactly as if it had been launched vertically. The laws of motion in one dimension are independent of any motion in the other dimensions. This leads to the idea that the laws of motion (and all other laws of physics) are equally valid in any inertial frame: the principle of relativity. This principle implies that no inertial frame can be considered “really stationary” or “really moving.” There is no absolute standard of velocity (contrast this with acceleration where Newton’s first law provides an absolute standard). We discuss some apparent counterexamples in everyday experience, and show how everyday experience can be misleading.

The Pedaling Technique of Elite Endurance Cyclists: Changes with Increasing Workload at Constant Cadence

1991 ◽  
Vol 7 (1) ◽  
pp. 29-53 ◽  
Author(s):  
Steven A. Kautz ◽  
Michael E. Feltner ◽  
Edward F. Coyle ◽  
Ann M. Baylor
Keyword(s):  
Vertical Component ◽  
Horizontal Component ◽  
Applied Force ◽  
The Other ◽  
Total Work ◽  
External Work ◽  
High Workload ◽  
Work Done ◽  
Positive Work

A pedal dynamometer recorded changes in pedaling technique (normal and tangential components of the applied force, crank orientation, and pedal orientation) of 14 elite male 40-km time trialists who rode at constant cadence as the workload increased from similar to an easy training ride to similar to a 40-km competition. There were two techniques for adapting to increased workload. Seven subjects showed no changes in pedal orientation, and predominantly increased the vertical component of the applied force during the downstroke as the workload increased. In addition to increasing the vertical component during the downstroke, the other subjects also increased the toe up rotation of the pedal throughout the downstroke and increased the horizontal component between 0° and 90°. A second finding was that negative torque about the bottom bracket during the upstroke usually became positive (propulsive) torque at the high workload. However, while torque during the upstroke did reduce the total positive work required during the downstroke, it did not contribute significantly to the external work done because 98.6% and 96.3 % of the total work done at the low and high workloads, respectively, was done during the downstroke.

Visual Illusion in Lengths of Words: An Old Friend in Disguise

1968 ◽  
Vol 23 (3) ◽  
pp. 932-934
Author(s):  
Glenn A. Moyer ◽  
W. H. Tedford
Keyword(s):  
Visual Illusion ◽  
Vertical Component ◽  
Horizontal Component ◽  
The Other ◽  
Visual Distortion ◽  
Apparent Length ◽  
The Difference

Pairs of words containing the same numbers of letters were found to differ in apparent length if one member of the pair contained all short letters while the other contained some tall letters such as b or l. It was hypothesized that the difference was due to a visual distortion whereby the horizontal component of a word appeared to be shortened when its vertical component was increased.

scholarly journals Time Dilation and the Equivalence of Inertial Frames

2021 ◽  
Author(s):  
Chandru Iyer ◽  
G. M. Prabhu
Keyword(s):  
Inertial Frame ◽  
Time Dilation ◽  
Three Dimensions ◽  
Relativity Theory ◽  
One Dimension ◽  
Dimensional Manifold ◽  
Principle Of Relativity ◽  
Inertial Frames ◽  
Ontological Concept ◽  
The Continuum

Abstract It is well known that simultaneity within an inertial frame is defined in relativity theory by a convention or definition. This definition leads to different simultaneities across inertial frames and the well-known principle of relativity of simultaneity. The lack of a universal present implies the existence of past, present and future as a collection of events on a four dimensional manifold or continuum wherein three dimensions are space like and one dimension is time like. However, such a continuum precludes the possibility of evolution of future from the present as all events exist ‘forever’ so to speak on the continuum with the tenses past, present and future merely being perceptions of different inertial frames. Such a far-reaching ontological concept, created by a mere convention, is yet to gain full acceptance. In this paper, we present arguments in favour of an absolute present, which means simultaneous events are simultaneous in all inertial frames, and subscribe to evolution of future from the present.

scholarly journals Assessing a Linear Nanosystem's Limiting Reliability from its Components

2008 ◽  
Vol 45 (03) ◽  
pp. 879-887 ◽  
Author(s):  
Nader Ebrahimi
Keyword(s):  
Present State ◽  
Size Range ◽  
Two Dimensions ◽  
The Other ◽  
One Dimension ◽  
Present Moment ◽  
One Dimensional ◽  
The One ◽  
Fixed Moment ◽  
Nanosized Systems

Nanosystems are devices that are in the size range of a billionth of a meter (1 x 10-9) and therefore are built necessarily from individual atoms. The one-dimensional nanosystems or linear nanosystems cover all the nanosized systems which possess one dimension that exceeds the other two dimensions, i.e. extension over one dimension is predominant over the other two dimensions. Here only two of the dimensions have to be on the nanoscale (less than 100 nanometers). In this paper we consider the structural relationship between a linear nanosystem and its atoms acting as components of the nanosystem. Using such information, we then assess the nanosystem's limiting reliability which is, of course, probabilistic in nature. We consider the linear nanosystem at a fixed moment of time, say the present moment, and we assume that the present state of the linear nanosystem depends only on the present states of its atoms.

Is There a Place for Anthropology in Social Science History?

1999 ◽  
Vol 23 (4) ◽  
pp. 535-559
Author(s):  
Alice Bee Kasakoff
Keyword(s):  
Social Science ◽  
The Other ◽  
One Dimension ◽  
Time And Space ◽  
Science History ◽  
Social Science History ◽  
Secure Place

Imagine a fourfold table in which one dimension is “present versus past” and the other “exotic versus home.” Traditionally, social and cultural anthropology’s domain has been the exotic’s present and history’s domain the home’s past. A third box, the home’s present, has been occupied by sociology, while the fourth, the exotic’s past, has usually been the province of anthropologists too because other disciplines—with the exception, perhaps, of ethnohistorians—are usually even less interested in exotic peoples’ past than in their present. These domains are now in flux. I argue, in what follows, that only when the oversimplified ideas about time and space that have created them are seriously questioned will anthropology find a secure “place” in social science history.

Peripheral representation of antennal orientation by the scapal hair plate of the cockroach Periplaneta americana

2001 ◽  
Vol 204 (24) ◽  
pp. 4301-4309 ◽  
Author(s):  
J. Okada ◽  
Y. Toh
Keyword(s):  
Single Unit ◽  
Periplaneta Americana ◽  
Vertical Component ◽  
Horizontal Component ◽  
Vertical Position ◽  
Horizontal Position ◽  
Joint Movement ◽  
Basal Segment ◽  
Dynamic Phase ◽  
Hair Sensilla

SUMMARY Arthropods have hair plates that are clusters of mechanosensitive hairs, usually positioned close to joints, which function as proprioceptors for joint movement. We investigated how angular movements of the antenna of the cockroach (Periplaneta americana) are coded by antennal hair plates. A particular hair plate on the basal segment of the antenna, the scapal hair plate, can be divided into three subgroups: dorsal, lateral and medial. The dorsal group is adapted to encode the vertical component of antennal direction, while the lateral and medial groups are specialized for encoding the horizontal component. Of the three subgroups of hair sensilla, those of the lateral scapal hair plate may provide the most reliable information about the horizontal position of the antenna, irrespective of its vertical position. Extracellular recordings from representative sensilla of each scapal hair plate subgroup revealed the form of the single-unit impulses in response to hair deflection. The mechanoreceptors were characterized as typically phasic-tonic. The tonic discharge was sustained indefinitely (>20 min) as long as the hair was kept deflected. The spike frequency in the transient (dynamic) phase was both velocity- and displacement-dependent, while that in the sustained (steady) phase was displacement-dependent.

scholarly journals Adult’s Participation in Work-related Training: The Balance between Improving Job and a Desire for Learning

2016 ◽  
Vol 6 (1) ◽  
pp. 1
Author(s):  
Ana Inés Renta Davids ◽  
Manel Fandos-Garrido ◽  
José Miguel Jiménez-González ◽  
Ángel Pío González-Soto
Keyword(s):  
Factor Analysis ◽  
Quantitative Analysis ◽  
Continuing Education ◽  
Professional Training ◽  
Demographic Variables ◽  
The Other ◽  
One Dimension ◽  
Work Related ◽  
Different Types ◽  
Motivation To Participate

<p>The study draws on findings from a survey of adults in non-formal continuing education under the professional training for employment framework in Spain. Quantitative analysis was carried out to a sample of 425 respondents from three different educational providers. Firstly, a factor analysis was conducted to fourteen motives for participation items. A two-dimension model of motivation to participate was identified: one dimension oriented towards job-improvement and the other dimension oriented towards learning. Secondly, a variance analysis was conducted according to demographics variables. Results showed significant statistical differences in the first dimension according to demographic variables. This might indicates an instrumental motivation in participation in work-related training among different groups who try to cope with different types of drawbacks.</p>

scholarly journals The role of morality in social cognition

2019 ◽  
Author(s):  
Jennifer Lauren Ray ◽  
Peter Mende-Siedlecki ◽  
Ana P. Gantman ◽  
Jay Joseph Van Bavel
Keyword(s):  
Social Cognition ◽  
Social Perception ◽  
Impression Formation ◽  
Factor Models ◽  
The Other ◽  
One Dimension ◽  
Primary Role ◽  
The Past ◽  
Important Basis

Over the past few decades, two-factor models of social cognition have emerged as the dominant framework for understanding impression formation. Despite the differences in the labels, there is wide agreement that one dimension reflects sociability potential, and the other, competence. One way in which the various two-factor models do clearly differ, however, is in the way the dimensions incorporate or produce evaluations of morality. Aristotle saw morality as the most important basis on which to form positive evaluations, because competence and sociability could only be virtuous, sincere, and trustworthy if expressed through a moral character. This chapter highlights research demonstrating the unique and possibly primary role of morality in social cognition. We clarify the dynamic, interactive, and conjoint effects of morality on social perception, and argue morality, competence, and sociability are three influential and interactive dimensions of social perception.

scholarly journals Comparison between sprinkler irrigation and natural rainfall based on droplet diameter

2016 ◽  
Vol 14 (1) ◽  
pp. e1201 ◽  
Author(s):  
MaoSheng Ge ◽  
Pute Wu ◽  
Delan Zhu ◽  
Daniel P. Ames
Keyword(s):  
Soil Erosion ◽  
Kinetic Energy ◽  
Droplet Diameter ◽  
Vertical Component ◽  
Radial Distance ◽  
Sprinkler Irrigation ◽  
Application Rate ◽  
Horizontal Component ◽  
Natural Rainfall ◽  
Actual Field

<p>An indoor experiment was conducted to analyze the movement characteristics of different sized droplets and their influence on water application rate distribution and kinetic energy distribution. Radial droplets emitted from a Nelson D3000 sprinkler nozzle under 66.3, 84.8, and 103.3 kPa were measured in terms of droplet velocity, landing angle, and droplet kinetic energy and results were compared to natural rainfall characteristics. Results indicate that sprinkler irrigation droplet landing velocity for all sizes of droplets is not related to nozzle pressure and the values of landing velocity are very close to that of natural rainfall. The velocity horizontal component increases with radial distance while the velocity vertical component decreases with radial distance. Additionally, landing angle of all droplet sizes decreases with radial distance. The kinetic energy is decomposed into vertical component and horizontal component due to the oblique angles of droplet impact on the surface soil, and this may aggravate soil erosion. Therefore the actual oblique angle of impact should be considered in actual field conditions and measures should be taken for remediation of soil erosion if necessary.</p>

Single-station SVD-based polarization filtering of ground roll: Perfection and investigation of limitations and pitfalls

Geophysics ◽  
2012 ◽  
Vol 77 (2) ◽  
pp. V41-V59 ◽  
Author(s):  
Olena Tiapkina ◽  
Martin Landrø ◽  
Yuriy Tyapkin ◽  
Brian Link
Keyword(s):  
Time Window ◽  
Synthetic Data ◽  
Vertical Component ◽  
Horizontal Component ◽  
Frequency Bandwidth ◽  
Polarization Filter ◽  
Data Set ◽  
Single Station ◽  
Ground Roll ◽  
Polarization Filtering

The advent of single receiver point, multi-component geophones has necessitated that ground roll be removed in the processing flow rather than through acquisition design. A wide class of processing methods for ground-roll elimination is polarization filtering. A number of these methods use singular value decomposition (SVD) or some related transformations. We focus on a single-station SVD-based polarization filter that we consider to be one of the best in the industry. The method is comprised of two stages: (1) ground-roll detection and (2) ground-roll estimation and filtering. To detect the ground roll, a special attribute dependent on the singular values of a three-column matrix formed by a sliding time window is used. The ground roll is approximated and subtracted using the first two eigenimages of this matrix. To limit the possible damage to the signal, the filter operates within the record intervals where the ground roll is detected and within the ground-roll frequency bandwidth only. We improve the ground-roll detector to make it theoretically insensitive to ambient noise and more sensitive to the presence of ground roll. The advantage of the new detector is demonstrated on synthetic and field data sets. We estimate theoretically and with synthetic data the attenuation of the underlying reflections that can be caused by the polarization filter. We show that the underlying signal always loses almost all the energy on the vertical component and on the horizontal component in the ground-roll propagation plane and within the ground-roll frequency bandwidth. The only signal component, if it exists, that can retain a significant part of its energy is the horizontal component orthogonal to the above plane. When 2D 3C field operations are conducted, the signal particle motion can deviate from the ground-roll propagation plane and can therefore retain some of its energy due to a set of offline reflections. In the case of 3D 3C seismic surveys, the reflected signal always deviates from the ground-roll propagation plane on the receiver lines that do not contain the source. This is confirmed with a 2.5D 3C synthetic data set. We discuss when the ability of the filter to effectively subtract the ground roll may, or may not, allow us to ignore the inevitable harm that is done to the underlying reflected waves.

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