Matters relating to length and duration in physics and transportation
I’ve written that the perspective of 1D space + 3D time is just as legitimate as the usual 3D space + 1D time. Is there an intermediate perspective of 2D space + 2D time? In a sense, Yes. This is the perspective of 2D images. Maps are usually 2D images of space but they may […]
The value of an independent variable may be selected first, and so is arbitrary, even subjective. One may select anything or everything within its range. A graph normally covers a whole range of the independent variable. Given an independent time interval, different travel rates result in different travel distances or, the other way around, different
Space is measured from a specified point, which is called an origin or zero point in space. The spatial location of all other points in space are relative to this zero point. The zero point may represent “here” from which other locations near and far are measured. Or the zero point may be a beginning
Clocks can easily be placed on moving bodies or observers to measure travel time continuously. A moving body can have on-board devices to measure cumulative travel distance. Observers have more difficulty measuring the cumulative travel distance of an external body but it can be done by motion tracking devices. If the distance is long, multiple
This post follows the previous one on circular motion. A timeline shows a linear representation of time (click to enlarge): A calendar can be linear, too: Linear calendars and clocks could be thought of as representing a kind of distance. It’s as if a clock were fastened to a wheel moving along a line. The
Consider two circular motions, one a wheel and the other a clock (click for animations): The wheel is the target motion to be measured. The clock is the reference motion, which maintains a constant angular velocity.
As I’ve noted several times, the physics of the observer takes duration as the dependent variable and measures the corresponding length or other variable. This fits well with the finding that gravity is an approximately constant acceleration, g, which equals 9.81 m/s². What is gravity in the context of an independently chosen distance and dependent
I’ve written about the inverse perspectives of travelers and shippers versus observers and scientists here. This post focuses on the language used, primarily the expectation of what motions larger or smaller values of measures correspond to. For an observer we’re accustomed to larger values corresponding to faster, more powerful motions. But travelers are usually trying
People have purpose and goals but natural science excludes final causes. People plan and design but natural science excludes formal causes. In that case call the science of formal and final (be)causes “hypernatural science”. These higher causes are not against nature (unlike supernatural) but are not inherent to nature (and so hypernatural). A physics for
Following the previous post on uniform motion, this post covers non-uniform motion in space and time. A simple way to get non-uniform motion is to join two uniform motions in different directions; the change in direction means the joint motion is non-uniform. Another way to get non-uniform motion is to accelerate at a constant rate.
