Mechanics Map (Penn State University)
OER Reviewed: University Physics Volume 3 (OpenStax)
Reviewer: Seach Chyr (Ernest) Goh, Assistant Professor of Teaching, School of Engineering, UBC Okanagan
Rating
Each criterion asks the reviewer to rate it on a scale of 1 to 5 (1 = very poor and 5 = excellent).
Comprehensiveness – Rating: 3
It covers a good majority of the elementary topics in Statics. However, inadequate or missing topics are:
- Thorough explanation of unit vectors.
- Thorough explanation of 3D force vectors as a main section with sufficient worked examples and homework problems.
- Simplification of a system of forces to a single force (in 2D and parallel cases) and to a wrench (2D case)
- 3D equilibrium, no example in the lecture, only ONE homework problem.
- Internal forces in beams.
- Appendices A & B in this report shows the missing topics compared to popular textbooks. Those highlighted in yellow are topics that would reasonably be expected to be covered in 1st or 2nd year.
- A glossary is not present.
Content Accuracy – Rating: 4
Content, including diagrams and other supplementary material, is accurate, error-free, and unbiased.
The content is generally accurate. However, Chapter 4 Video Introduction, sections 4.2, 6.4 and 7.4 require major corrections. Minor corrections are listed in Appendix A of this report.
Relevance/Longevity – Rating: 4
Content is up-to-date, but not in a way that will quickly make the OER obsolete within a short period of time. The OER is written and/or arranged in such a way that necessary updates will be relatively easy and straightforward to implement.
As this is a fundamental subject in engineering, content taken from recent times is likely to be relevant for the foreseeable future. However, this is not written in a Wiki form that can be updated by all users. Updates can only be made by the author. The mechanism for reporting errors is by email to the author. If he runs this OER alone, response times could be dependent on how busy he is.
Clarity – Rating: 4
The OER is written in lucid, accessible prose, and provides adequate context for any jargon/technical terminology used.
The prose is clear and concise. However, certain areas would benefit from more elaboration or additional labelling, as listed in the appendices of this report.
Consistency – Rating: 4
The OER is internally consistent in terms of terminology and framework.
Consistency is generally good. The major inconsistency is the mix of both oblique and axonometric projection in figures. Ideally, all figures involving 3D analysis should be in axonometric projection. Other inconsistencies among different sections and between video and page are listed in the appendices of this report.
Modularity – Rating: 5
The OER is easily and readily divisible into smaller reading sections that can be assigned at different points within the course (i.e., enormous blocks of text without subheadings should be avoided). The OER should not be overly self-referential, and should be easily reorganized, and realigned with various subunits of a course without presenting much disruption to the reader.
Excellent modularity. In a few places in Appendix A, I have suggested covering certain sections ahead of others, and these are possible with the modular organization of the content. For dynamics, many sections are advanced but the modularity means that selected elementary sections can be used.
Organization/Structure/Flow – Rating: 4
The topics in the OER are presented in a logical, clear fashion.
Topics are presented in a logical fashion. A video introduction gives an overview of each chapter. However, I have two major suggestions on improving the sequence of topics:
- Free body diagrams should come after Newton’s Laws, because the third Law is often required in FBDs.
- A more thorough teaching of vectors in the context of force and moment, currently placed in the appendices, should be a formal section before chapters 2 and 3.
Given the modularity of the content, re-scheduling of coverage by adopting instructors is not too difficult.
Interface – Rating: 4
The OER is free of significant interface issues, including navigation problems, distortion of images/charts, and any other display features that may distract or confuse the reader.
The biggest issue is that all WeBWork problems not working.
A less serious issue is that videos of worked problems come in whiteboard and doc cam styles, both of which are not ideal because of obstruction by the body or hand of the presenter. A better way is to use a Videoscribe-style video or a lightboard. The neatness of the solutions could be better.
Minor issues are: the title of each page does not have the section number; figures and equations do not have numbers.
Grammatical/Spelling Errors – Rating: 5
The OER contains no grammatical or spelling errors.
There are minor typo errors, listed in the appendices of this report.
Diversity and Inclusion – Rating: N/A
The OER reflects diversity and inclusion regarding culture, gender, ethnicity, national origin, age, disability, sexual orientation, education, religion. It does not include insensitive or offensive language in these areas.
I would consider this as a non-applicable criterion. The examples given are mostly of objects and do not contain human subjects or social situations. I recall seeing only one photo of a female youth.
Recommendation
- Do you recommend this resource for the specific course taught in the first-year engineering common curriculum (in place of a commercially available resource)?
With reference to PHYS 1 and PHYS 3 of the BCCAT 1st year engineering curriculum, I hesitate to recommend this resource. - If not, why? What improvements, if any, could be made?
It provides coverage of almost all the topics with the exception of:PHYS3 – Internal forces and parts of Moments. Most conspicuously, Rigid Body equilibrium in 3D, though superficially covered, is too brief (just 1 homework problem) for sufficient practice.
3D coordinate systems, in particular, cylindrical coordinate systems.
The instructor should have resources of his/her own to cover inadequacies mentioned above.
- What gaps in content have you identified?
In deciding whether to adopt a textbook, it is not just the quantitative criteria that need to be considered.Commercially available “textbooks” are no longer a bundle of paper with content printed on them. They are now a comprehensive service that includes computerized media, practice questions, adaptive exercises, etc. Instructors adopting a commercial textbook have much more resources at their disposal to design and deliver a course with active learning, interactivity, formative assessments and feedback, etc.
Students have access to more than what is examinable, and can use the textbook as a reference for fundamental derivations, related content beyond the prescribed syllabus, extra practice, video tutorials, animated media, etc.
The first weakness of this OER is that it merely moves the age-old printed content to a webpage, and the “sage on the stage” to a computer screen. The lesson videos do not harness the opportunity to animate, show in 3D or sequentiate explanations. The Worked Problem videos do sequentiate, however, because they are written out by hand, blending with animated and/or 3D views is not harnessed. The element of active learning is also missing.
A second weakness is that it covers the bare minimum of each topic it intends to cover. Frequently, fundamental knowledge, and extensions beyond simplest cases are omitted. Homework problems are severely limited and do not show interesting real-life scenarios that would help stimulate interest and curiosity.