Skip to main content Accessibility help
×
Hostname: page-component-586b7cd67f-t7fkt Total loading time: 0 Render date: 2024-11-25T13:34:18.009Z Has data issue: false hasContentIssue false

Discourse 2 of the Dioptrics

Published online by Cambridge University Press:  17 December 2009

Stephen Gaukroger
Affiliation:
University of Sydney
Get access

Summary

Later on we shall need to know how to determine this refraction quantitatively, and since the comparison I have just used [between the refraction of light and the penetration of a cloth by a tennis ball] enables this to be understood easily, I believe it is appropriate that I explain it here and now, and so as to make it easier to understand, I shall speak first about reflection. Suppose a ball [fig. 19] is struck from A toward B, and at point B meets the surface of the ground CBE, which prevents it from going further and causes it to be deflected: let us see in what direction it will go. But so that we do not get caught up in new difficulties, assume that the ground is perfectly flat and hard, and that the ball always travels at a constant speed, both when it descends and rebounds upwards, and let us ignore entirely the question of the power that continues to move it when it is no longer in contact with the racquet, as well as any effect of its weight, bulk, or shape. For we are not concerned here to examine it closely, and none of these things has a bearing on the action of light, which is what should concern us. We need only note that the power, whatever it be, which can make the motion of this ball continue, is different from that which determines it to move in one direction rather than another.

Type
Chapter
Information
Publisher: Cambridge University Press
Print publication year: 1998

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

Save book to Kindle

To save this book to your Kindle, first ensure [email protected] is added to your Approved Personal Document E-mail List under your Personal Document Settings on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part of your Kindle email address below. Find out more about saving to your Kindle.

Note you can select to save to either the @free.kindle.com or @kindle.com variations. ‘@free.kindle.com’ emails are free but can only be saved to your device when it is connected to wi-fi. ‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.

Find out more about the Kindle Personal Document Service.

Available formats
×

Save book to Dropbox

To save content items to your account, please confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account. Find out more about saving content to Dropbox.

Available formats
×

Save book to Google Drive

To save content items to your account, please confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account. Find out more about saving content to Google Drive.

Available formats
×