0.13 Phy1100: force -- vector solutions for coplanar forces concurrent  (Page 2/13)

Listings

• Listing 1 . Tent pole exercise.

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 .

General background information

Creation of tactile graphics

The module titled Manual Creation of Tactile Graphics explains how to create tactile graphics from svg files that I will provide.

If you are going to have an assistant create tactile graphics for this module, you will need to download the file named Phy1100.zip , which contains the svg files for this module. Extract the svg files from the zip file and provide them to your assistant.

Also, if you are going to use tactile graphics, it probably won't be necessary for you to perform the graph board exercises. However, you shouldstill walk through the graph board exercises in your mind because I will often embed important physics concepts in the instructions for doing the graph boardexercises.

In each case where I am providing an svg file for the creation of tactile graphics, I will identify the name of the appropriate svg file and display animage of the contents of the file for the benefit of your assistant. As explained here , those images will be mirror images of the actual images so that your assistant can emboss the image from the back ofthe paper and you can explore it from the front.

I will also display a non-mirror-image version of the image so that your assistant can easily read the text in the image.

Also in those cases, I will provide a table of key-value pairs that explain how the Braille keys in the image relate to textor objects in the image.

The law of sines

Much of the background material needed for this module was presented in the earlier module titled Introduction to Statics, Equilibrium, and Forces . However, beginning with this module, you will need some information ontrigonometry that was not presented in the earlier module titled Brief Trigonometry Tutorial . That item is known as the law of sines (see (External Link) ).

Proving identities

When I was a student in a trigonometry course many years ago, students were required to "prove identities" which was a process very similar to provingtheorems in plane geometry. That activity included doing such things as proving that the law of sines is true.

I don't know if mathematics instructors still require students to prove identities or not. In any event, we will simply accept such mathematical truthsin this collection of modules and won't worry about proving that they are true.

We will work through some exercises in this module to show how the law of sines can be used to advantage.

Beyond the right triangle

Previous modules using trigonometry have dealt almost exclusively with right triangles. Beginning in this module, we will start using trigonometry to solveproblems that involve triangles that are not right triangles.

Tactile graphics

The svg file that is required to create tactile graphics for this exercise is named Phy1100a1.svg. You should have downloaded that file earlier.