Question

learning objectives
after studying this chapter, you will be able to:

• define engine performance.
• define and compute bore and stroke.
• understand the concept of energy and differentiate between kinetic and potential energy.
• understand the concepts of force and pressure.
• explain the concepts of work, power, and torque.
• calculate an engines displacement and compression ratio.
• differentiate between the various types of engine horsepower.
• define and calculate engine torque.
• explain volumetric efficiency, practical efficiency, mechanical efficiency, and thermal efficiency.

instructions: after studying the chapter, complete the following questions and problems.

1. a measurement of the work an engine does and how well it does the work is referred to as engine ____.
2. engine ___ is the diameter or width across the top of the cylinder.
3. ___ is the up or down movement of the piston.
4. crank ___ is the distance from the centerline of the connecting rod journal to the centerline of the crankshaft.
5. stroke is equal to ___.

a. two times crank offset
b. the distance between tdc and bdc
c. both a and b.
d. neither a nor b.
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small gas engines workbook 41

Explanation:

1. Engine performance measures work and efficiency of an engine.
2. Bore is the diameter across the top of the cylinder.
3. Stroke is the up - down piston movement.
4. Crank offset is the distance from connecting rod journal to crankshaft centerline.
5. Stroke is two times crank offset and the distance between Top Dead Center (TDC) and Bottom Dead Center (BDC).

Answer:

1. performance
2. bore
3. stroke
4. offset
5. C. Both A and B.