Hmwk 1 Problems 1 Define engineering design Illustrate the e

Hmwk 1 Problems 1) Define engineering design. Illustrate the engineering design process/activity and elaborate on each important step/concept.

2)From the expression, “Build a better mousetrap and the world will beat a path to your door,” write a goal/problem statement and a set of at least six specifications that you would apply to a solution. Suggest at least three concepts, complete with sketches, to satisfy this statement.

3) Define what is ethics in the field of engineering and explain what is meant by ethical dilemma.

4) Convert a mass of 250 lbm to a) lbf , b) slug, c) kg.

5) Express a 68 kg mass in units of slugs and lbm. How much does this mass weigh in lbf and N on a) earth, b) moon and c) in earth orbit?

6) Convert a gear reducer torque of 20,000 in-lb to a) N-m and b) N-mm

7) What do the following initialisms stand for: a) ips; b) fps; c) cgs; d) SI? What are the three base units in each system? What is a derived unit in each system.

8) Name three of the several groups of machine elements and identify one engineering application for each group you name.

9) Provide two examples of each: a) design for failure and b) design not to fail. Explain what is important to the engineer and user for each example.

10) What is the trajectory of an un-struck golf ball?

Solution

3) Engineering ethics is the field of applied ethics and system of moral principles that apply to the practice of engineering. The field examines and sets the obligations by engineersto society, to their clients, and to the profession. As a scholarly discipline, it is closely related to subjects such as the philosophy of science, the philosophy of engineering, and theethics of technology.

A basic ethical dilemma is that an engineer has the duty to report to the appropriate authority a possible risk to others from a client or employer failing to follow the engineer\'s directions. According to first principles, this duty overrides the duty to a client and/or employer.^[29]An engineer may be disciplined, or have their license revoked, even if the failure to report such a danger does not result in the loss of life or health.

4) 250 lbm = 113.398 kg

     250 lbm = 7.77024 slugs

     250 lbm = 250 * 32.2 = 8050 lbf

5) 68 kg = 4.66 slugs

     68 kg = 149.914 lbm

     on Earth gravity = 9.8 m/s^2 or 32.2 ft/s^2

     Therefore weight = 68 * 9.8 = 666.4 N

                    weigth = 149.914 * 32.2 = 4837.32 lbf

     on moon gravity = 1.633 m/s^2 or 5.36667 ft/s^2

     Therefore weight = 68 * 9.8/6 = 1111.067 N

                    weigth = 149.914 * 32.2/6 = 806.22 lbf

     In earth\'s orbit gravity depends upon the distance of the orbit from the earth, which is not given

6) 20000 lb-in = 2259.7 Nm

    20000 lb-in = 2259700 Nmm

7) a) ips = inch pound second system uses inch pound and second as its basic units

    b) fps = foot pound second system uses foot pound and second as its basic units

    c) cgs = centimeter gram second system using centimeter gram second as its basic units

    d) SI = Standard International System uses meter kilogram and second as its basic units.