Read an Excerpt
101 Things I Learned in Engineering School
By Matthew Frederick, John Kuprenas
Grand Central PublishingCopyright © 2013 Matthew Frederick John Kuprenas
All rights reserved.
Engineering succeeds and fails because of the black box.
A black box is a conceptual container for the knowledge, processes, and working assumptions of an engineering specialty. On multidisciplinary design teams, the output of one discipline's black box serves as the input for the black boxes of one or more other disciplines. The designer of a fuel system, for example, works within a "fuel system black box" that produces an output for the engine designer; the engine designer's black box outputs to the automatic transmission designer, and so on.
Design solutions don't emerge linearly, however, and design teams work in interconnected webs of relationships. Hence, the black box model works best when employed as a momentary ideal that is adjusted and redefined throughout the design process as constraints become evident, opportunities emerge, prototypes are tested, and goals are clarified. It fails when expected to be permanent and orderly.CHAPTER 2
Civil engineering is the grandparent of all engineering.
In its early days during the Roman Empire, civil engineering was synonymous with military engineering. Their kinship was still strong when the first engineering school in America was founded in 1802 at the U.S. Military Academy at West Point, New York. USMA graduates planned, designed, and supervised the construction of much of the nation's early infrastructure, including roads, railways, bridges, and harbors, and mapped much of the American West.CHAPTER 3
The heart of engineering isn't calculation; it's problem solving.
School may teach the numbers first, but calculation is neither the front end of engineering nor its end goal. Calculation is one means among many to an end—to a solution that provides useful, objectively measurable improvement.CHAPTER 4
Every problem is built on familiar principles.
Every problem has embedded in it a "hook"—a familiar, elemental concept of statics, physics, or mathematics. When overwhelmed by a complex problem, identify those aspects of it that can be grasped with familiar principles and tools. This may be done either intuitively or methodically, as long as the tools you ultimately use to solve the problem are scientifically sound. Working from the familiar will either point down the path to a solution, or it will suggest the new tools and understandings that need to be developed.CHAPTER 5
Every problem is unique.
Engineering problems rely on the familiar, but invention is also called for. Some problem-solving tools are developed through rote and repetition; some emerge intuitively; some rote-learned tools become intuitive over time; and some come out of necessity and even desperation. Add the tools you develop from solving each problem to your toolbox to use on future problems. More importantly, add to your toolbox the methods by which you discovered the new tools.CHAPTER 6
"Inside every large problem is a small problem struggling to get out."
—TONY HOARECHAPTER 7
You are a vector.
A force is expressed graphically by a vector. A vector's length is its magnitude, and its direction is given in relation to the x, y, and z axes. Every person has a gravity force vector with a magnitude measured in pounds or newtons, and a direction toward the center of the earth. Any single vector can be replaced by more than one component vectors, and vice versa.CHAPTER 8
An object receives a force, experiences stress, and exhibits strain.
Force, stress, and strain are used somewhat interchangeably in the lay world and may even be used with less than ideal rigor by engineers. However, they have different meanings.
A force, sometimes called "load," exists external to and acts upon a body, causing it to change speed, direction, or shape. Examples of forces include water pressure on a submarine hull, snow loads on a bridge, and wind loads on the sides of a skyscraper.
Stress is the "experience" of a body—its internal resistance to an external force acting on it. Stress is force divided by unit area, and is expressed in units such as pounds per square inch.
Strain is a product of stress. It is the measurable percentage of deformation or change in an object, such as a change in length.CHAPTER 9
When a force acts on an object, three things can happen.
An object that receives a force will remain stationary, move, or change shape—or a combination. Mechanical engineering generally seeks to exploit movement, while structural engineering seeks to prevent or minimize it. Nearly all engineering disciplines aim to minimize changes in the shape of the designed object.CHAPTER 10
When a force acting on a fixed object increases, three things happen.
1. Proportional elongation: When an object, such as a steel bar, is subjected to a stretching (tensile) force, it initially will deform in proportion to the loads placed on it. If load x causes the bar to deform d, 2x will cause deformation 2d, 3x will cause 3d, and so on. If the load is removed, the bar will return to its original length.
2. Disproportional elongation: Beyond a certain point of loading (which varies among materials) an object will deform at a rate greater than the rate of increase in loading. If load 10x causes deformation 10d, load 10.5x may cause 20d. When the load is removed, the material will not quite return to its original length.
3. Ductility: If loading is further increased, the material will become visibly deformed and will soon fracture.CHAPTER 11
Four material characteristics
Stiffness/elasticity concerns the lengthening or shortening of a material under loading. Stiffness is resistance to change in length; elasticity is the ability to return to original size and shape. Stiffness is measured formally by the modulus of elasticity, which is the slope of the straight line portion of the stress-strain curve: the steeper, the stiffer.
Strength is a measure of a material's ability to accept a load. The maximum strength of a material (usually tested in tension rather than compression) is represented by the highest point on the stress-strain curve.
Ductility/brittleness is the extent a material deforms or elongates before fracturing. A highly ductile material is taffy-like, and its stress- strain curve extends far to the right. A very brittle material is chalklike; its curve ends abruptly after reaching maximum strength.
Toughness is an overall measure of a material's ability to absorb energy before fracture. It is represented by the total area under the stress-strain curve.
Excerpted from 101 Things I Learned in Engineering School by Matthew Frederick, John Kuprenas. Copyright © 2013 Matthew Frederick John Kuprenas. Excerpted by permission of Grand Central Publishing.
All rights reserved. No part of this excerpt may be reproduced or reprinted without permission in writing from the publisher.
Excerpts are provided by Dial-A-Book Inc. solely for the personal use of visitors to this web site.