Mechanical Engineering Principles

Citation

Bird, J., & Ross, C. (2020). Mechanical Engineering Principles (4th ed.). Routledge.

Chapter Summary

The fourth edition runs to 388 pages in four parts and 28 short chapters, most between about six and twenty pages long. Revision tests are placed after every few chapters, and the book ends with a list of formulae, metric–imperial conversions, the Greek alphabet, a glossary and answers to the multiple-choice questions. Routledge counts 400 fully worked problems, 700 further problems with answers and 300 multiple-choice questions across the book.

Chapters 1–2: Revisionary mathematics; Further revisionary mathematics

Part One, "Revision of Mathematics": two chapters revise the mathematics used in the rest of the book, each followed by its own revision test. They let a reader whose mathematics is rusty catch up before any mechanics begins.

Chapters 3–6: The effects of forces on materials; Tensile testing; Forces acting at a point; Simply supported beams

Part Two, "Statics and Strength of Materials", opens with what forces do to materials, how a tensile test characterises them, the resolution of forces acting at a point, and the reactions of simply supported beams.

Chapters 7–9: Forces in structures; Bending moment and shear force diagrams; First and second moments of area

Analysis of forces in structures, then the internal shear force and bending moment in beams and the section properties needed for bending.

Chapters 10–12: Bending of beams; Torque; Twisting of shafts

Stress in bent beams, then torque and the twisting of shafts, the two classic loading cases of elementary strength of materials.

Chapters 13–14: An introduction to matrix algebra; The matrix displacement method

The two chapters new to this edition. Routledge says the matrix displacement chapter includes guidance on software that can be run on smartphones, tablets or laptops. At about twenty pages, the matrix displacement chapter is one of the longest in Part Two.

Chapters 15–18: Linear and angular motion; Linear momentum and impulse; Force, mass and acceleration; Work, energy and power

Part Three, "Dynamics", begins with the core of elementary dynamics: kinematics of linear and angular motion, momentum and impulse, Newton's second law, and work, energy and power.

Chapters 19–22: Friction; Motion in a circle; Simple harmonic motion; Simple machines

Further dynamics topics: friction, circular motion, simple harmonic motion, and simple machines.

Chapters 23–24: Heat energy and transfer; Thermal expansion

Part Four, "Heat Transfer and Fluid Mechanics", opens with a short introduction to heat as energy, its transfer, and the expansion of materials with temperature.

Chapters 25–28: Hydrostatics; Fluid flow; Ideal gas laws; The measurement of temperature

Fluids at rest and in motion, the ideal gas laws and methods of measuring temperature close the book.

Key Concepts

Part One (Chapters 1–2)

• Revisionary mathematics: the algebra and other techniques the book uses, revised at the start so that the mechanics chapters can rely on them.

Part Two (Chapters 3–14)

• Tensile testing: the standard test that characterises how a material behaves under tension.
• Forces acting at a point: combining and resolving forces that act through one point.
• Bending moment and shear force diagrams: plots of the internal forces along a beam.
• First and second moments of area: section properties used in beam calculations.
• Matrix displacement method: a matrix-based method of structural analysis, introduced with its matrix-algebra background.

Part Three (Chapters 15–22)

• Linear momentum and impulse: the momentum of a body and the change produced by a force acting over time.
• Work, energy and power: energy-based descriptions of motion.
• Simple harmonic motion: the basic oscillation, introduced at an elementary level.
• Simple machines: basic devices that change the size or direction of a force, the last topic of the dynamics part.

Part Four (Chapters 23–28)

• Hydrostatics: pressure and forces in fluids at rest.
• Ideal gas laws: the relations between pressure, volume and temperature of a gas.

Critical Analysis

Strengths

• Very large practice set. Routledge's figures (400 worked problems, 700 further problems with answers, 300 multiple-choice questions) are high for a book of under 400 pages. Regular revision tests after every two to four chapters give natural checkpoints.
• Gentle entry. Opening with two chapters of revisionary mathematics and keeping chapters short makes the book usable by students whose mathematics is not yet secure, including those entering engineering through further-education routes. Routledge states the edition matches the latest BTEC National specifications and can also be used on undergraduate courses in several engineering disciplines.
• Breadth in one volume. Statics, strength of materials, dynamics, heat transfer and fluid mechanics sit in one book, which suits foundation and first-year courses that touch all of them briefly.
• Support material. A companion website offers fully worked solutions to the problems and revision tests, practical demonstration videos, a glossary and notes on the engineers mentioned in the text.

Limitations

• Shallow treatment by design. With 28 chapters in 388 pages, each topic gets only a short chapter; Chapter 10 on bending of beams, for example, occupies about six pages. Students on a full university statics or mechanics-of-materials course will need a fuller text.
• Some topics stand slightly apart. Part Four on heat transfer, fluids, gas laws and temperature measurement goes beyond statics and dynamics, and the two new matrix chapters introduce a computer-oriented method of structural analysis that many first statics modules do not cover. Courses may skip or postpone them.
• Vocational framing. The alignment with BTEC National specifications, and Bird's background in further-education teaching, shape the level. University students should expect an introductory pace and use the book as a starting point rather than a complete course text.

Where It Fits in the Course

In this statics and dynamics course, Bird and Ross is the most elementary text and the one with the widest scope. Hibbeler's Engineering Mechanics: Statics and Meriam and Kraige's Engineering Mechanics: Dynamics are the full university treatments, with extensive problem sets and, in Meriam and Kraige, a systematic vector approach; Bird and Ross can be used before them to build confidence, or alongside them as a source of short explanations and extra drill. The free OpenStax University Physics Volume 1 covers the calculus-based physics behind the same mechanics topics.

Rao's Mechanical Vibrations and Williams's Fundamentals of Applied Dynamics belong much later: Bird and Ross's single chapter on simple harmonic motion is only a first glimpse of what Rao develops in full, and Williams's work-energy, momentum and Lagrangian methods assume a solid first course in dynamics.

How to Use This Book

The book is aimed at students starting engineering at further-education level or in the first year of a degree, and Routledge also lists it for undergraduate courses in mechanical, civil, structural, aeronautical and marine engineering and naval architecture. Readers need school mathematics; the opening chapters revise what the book uses.

A practical plan:

• Start with the mathematics: attempt the Part One revision tests first. If they go smoothly, move on; if not, work through Chapters 1–2 properly.
• Statics and materials: Chapters 3–12 in order form the core for a statics or introductory strength-of-materials module. Leave Chapters 13–14 until the matrix method is needed, or use them as an introduction to computer-based structural analysis.
• Dynamics: Chapters 15–22 in order. Chapter 21 makes a useful preview before a vibrations course.
• Optional: Part Four, unless the course covers heat and fluids.

Use the worked problems as models, then do the further problems and check the answers; use each revision test as a timed self-assessment before moving to the next block. When a topic is assessed in more depth than the book provides, go on to the matching chapter of a full statics or dynamics text.