Table of contents
Preface
General
This module is part of a book (or collection) designed to make physics concepts accessible to blind students. The collection is intended to supplement but not toreplace the textbook in an introductory course in high school or college physics.
This module introduces force and motion in a format that is accessible to blind students.
Prerequisites
In addition to an Internet connection and a browser, you will need the following tools (as a minimum) to work through the exercises in these modules:
- A graph board for plotting graphs and vector diagrams ( (External Link) ).
- A protractor for measuring angles ( (External Link) ).
- An audio screen reader that is compatible with your operating system, such as the NonVisual Desktop Access program (NVDA), which is freelyavailable at (External Link) .
- A refreshable Braille display capable of providing a line by line tactile output of information displayed on the computer monitor ( (External Link) ).
- A device to create Braille labels. Will be used to label graphs constructed on the graph board.
The minimum prerequisites for understanding the material in these modules include:
- A good understanding of algebra.
- An understanding of the use of a graph board for plotting graphs and vector diagrams ( (External Link) ).
- An understanding of the use of a protractor for measuring angles ( (External Link) ).
- A basic understanding of the use of sine, cosine, and tangent from trigonometry ( (External Link) ).
- An introductory understanding of JavaScript programming ( (External Link) and (External Link) ).
- An understanding of all of the material covered in the earlier modules in this collection.
Supplemental material
I recommend that you also study the other lessons in my extensive collection of online programming tutorials. You will find a consolidated index at www.DickBaldwin.com .
Discussion
We dealt with bodies in equilibrium in earlier modules. By equilibrium, I mean that we dealtwith forces acting on bodies at rest or forces acting on bodies in uniform motion. A body in equilibrium does not accelerate as a result of the forces acting onit.
An example of a body experiencing forces while at rest
A highway bridge is an example of a body at rest being acted upon by a variety of forces.As vehicles enter and exit the bridge, those vehicles exert forces on the bridge. The impact of those forces is "felt" by all the structural members that make up the bridge.The tension and compression in the various members of the bridge change as vehicles enter and leave the bridge, but the bridge remains in the same fixedlocation. If properly designed, the bridge doesn't experience acceleration and crash into the river below as a result of those changing forces.