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ANSWER TO REVIEW QUESTION: Machine Design Elements

Here are the answer to the questions on Machine Design posted here last week.

1. A type of bearing lubrication that produces a complete physical separation of the sliding surfaces resulting in low friction and long wear-free service life called_____.
Answer: A. Hydrodynamic

2. This type of bearing is used either to absorb shaft loads or to position the shaft axially.
Answer: B. Thrust bearing




3. Property of a bearing material to withstand repeated load application without cracking or flaking.
Answer: C. Fatigue resistance

4. It is a structural system constructed of linear members forming triangular patterns.
Answer: B. Truss

5. It is defined as the state of lateral instability that occurs when a long member is stressed below the yield point.
Answer: A. Elastic buckling



6. In foundry and molding, green sand refers to sand combined with
Answer: D. Clay and Bentonite

7. Machining process where material is removed by focusing high-velocity electrons on the work piece.
Answer: C. electron-beam machining

8. Machining process where water is ejected from a nozzle at pressures as high as 200,000 lb/in2 (1,400 MPa) and acts as a saw.
Answer: D. water jet machining




9. A welding technique where an external supply of gas, such as carbon dioxide, or by gas generated when the electrode flux heats up is used to protect the molten metal from atmospheric contaminants that may result in poor weld quality.
Answer: A. Gas shielding

10. In an automobile, it is a unit attached to the ring gear which equalizes the traction of both wheels and permits one wheel to turn faster than the other, as needed on curves.
Answer: B. Differential

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Past Mechanical Engineering Board Exam Question Number 1
A 4 inches diameter short shaft carrying 2 pulleys close to the bearings transmits how much horsepower if the shaft makes 120 rpm.

A.200HP               B. 199 HP

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