The Nature of Physical Theory: A Study in Theory of Knowledge

By Victor F. Lenzen | Go to book overview

CHAPTER IV
KINEMATICS

1. KINETICS OF A POINT

IN the preceding chapters we have considered the concepts of geometrical properties, especially the concepts of geometrical quantities such as the measure of distance, angle, etc., and further the concepts of temporal properties and of temporal quantities such as the measure of time interval. In the general sense these are all physical quantities: they are measure numbers which are assigned to measurable characters. The quantities are referred to as: the distance, the angle, the x coordinate, the time. In the present chapter we shall take up the concepts of quantities which serve to describe motion, The subject matter of this chapter is kinematics, which may be characterized as the description of motion. Inasmuch as motion is change of position in space with time, the quantities of kinematics are to be defined in terms of geometrical and temporal quantities.

The fundamental condition for the description of motion is the choice of a frame of reference. The representation of the motion of any body depends upon the frame of reference employed, as can be seen from a simple example. Suppose that a train is moving along a straight track, and a man in the train drops a stone out of the window. What is the path of the stone? The man in the train would use the car as a frame of reference, and relative to this frame the stone moves in a straight line. An observer on the ground would choose the surface of the earth as a frame of reference, and relative to it the stone moves in a parabolic path. Relative to a frame attached to the sun the path would be still different. Thus the description of motion presupposes the selection of a frame

-85-

Notes for this page

Add a new note
If you are trying to select text to create highlights or citations, remember that you must now click or tap on the first word, and then click or tap on the last word.
One moment ...
Default project is now your active project.
Project items
Notes
Cite this page

Cited page

Style
Citations are available only to our active members.
Buy instant access to cite pages or passages in MLA 8, MLA 7, APA and Chicago citation styles.

(Einhorn, 1992, p. 25)

(Einhorn 25)

(Einhorn 25)

1. Lois J. Einhorn, Abraham Lincoln, the Orator: Penetrating the Lincoln Legend (Westport, CT: Greenwood Press, 1992), 25, http://www.questia.com/read/27419298.

Note: primary sources have slightly different requirements for citation. Please see these guidelines for more information.

Cited page

Bookmark this page
The Nature of Physical Theory: A Study in Theory of Knowledge
Table of contents

Table of contents

Settings

Settings

Typeface
Text size Smaller Larger Reset View mode
Search within

Search within this book

Look up

Look up a word

  • Dictionary
  • Thesaurus
Please submit a word or phrase above.
Print this page

Print this page

Why can't I print more than one page at a time?

Help
Full screen
Items saved from this book
  • Bookmarks
  • Highlights & Notes
  • Citations
/ 308

matching results for page

    Questia reader help

    How to highlight and cite specific passages

    1. Click or tap the first word you want to select.
    2. Click or tap the last word you want to select, and you’ll see everything in between get selected.
    3. You’ll then get a menu of options like creating a highlight or a citation from that passage of text.

    OK, got it!

    Cited passage

    Style
    Citations are available only to our active members.
    Buy instant access to cite pages or passages in MLA 8, MLA 7, APA and Chicago citation styles.

    "Portraying himself as an honest, ordinary person helped Lincoln identify with his audiences." (Einhorn, 1992, p. 25).

    "Portraying himself as an honest, ordinary person helped Lincoln identify with his audiences." (Einhorn 25)

    "Portraying himself as an honest, ordinary person helped Lincoln identify with his audiences." (Einhorn 25)

    "Portraying himself as an honest, ordinary person helped Lincoln identify with his audiences."1

    1. Lois J. Einhorn, Abraham Lincoln, the Orator: Penetrating the Lincoln Legend (Westport, CT: Greenwood Press, 1992), 25, http://www.questia.com/read/27419298.

    Cited passage

    Thanks for trying Questia!

    Please continue trying out our research tools, but please note, full functionality is available only to our active members.

    Your work will be lost once you leave this Web page.

    Buy instant access to save your work.

    Already a member? Log in now.

    Search by... Author
    Show... All Results Primary Sources Peer-reviewed

    Oops!

    An unknown error has occurred. Please click the button below to reload the page. If the problem persists, please try again in a little while.