### Mechanical Board Exam Review Questions: THERMODYNAMICS

In preparation for the second phase of Mechanical Engineer Board Exam this coming October 2010 and that of the "Overseas" version of it, I have here some review questions on Thermodynamics.

Instruction: Choose the best answer among the given choices.

1. The state of a simple substance can be defined by at least how many properties (e.g. pressure, mass, temperature, density)?
a. One
b. Two
c. Three
d. Four

2. The ability of a heat engine to convert the supplied heat to work is referred to as…
a. Thermal efficiency
b. Efficiency
c. Coefficient of performance
d. Coefficient of efficiency

3. To increase the efficiency of a Carnot cycle…
a. Increase the maximum temperature
b. Decrease the minimum temperature
c. Both a and b
d. Increase both the maximum and minimum temperatures

4. The area under the curve of the process plotted in the p-V diagram corresponds to…
a. Work flow
b. Work non-flow
d. Heat

5. The value of n, in the equation PVn=C when the process is isothermal?
a. 1
b. 1.4
c. K
d. 0

6. The value of n, in the equation PVn=C when the process is isometric?
a. 1
b. K
c. Infinity
d. 0

7. In the T-s diagram, the area under the process curve corresponds to…
a. Heat of the process
b. Entropy of the process
c. The mean temperature of the process
d. The thermal efficiency of the process

8. What law of thermodynamics introduced the concept of entropy?
a. First Law of Thermodynamics
b. Second Law of Thermodynamics
c. Third Law of Thermodynamics
d. Zeroth law of Thermodynamics

9. A device that converts heat energy to shaft work.
a. Blackbody
b. Heat engine
c. Thermal cycle
d. Thermostat

10. A thermodynamic process characterized by a straight vertical line in the T-s diagram.
a. Isothermal process
c. Isochoric process
d. Isopiestic process

Answers will be provided soon...so watch out for this blog!

1. potang ina mo! e post mo na ang anser! pota!

### PAST MECHANICAL BOARD EXAM QUESTION: Machine Design Set-1 (solutions and answers)

The following are the solutions and answers to MODIFIED PAST MECHANICAL BOARD EXAM QUESTION: Machine Design Set-1 posted on this blog last Saturday, November 14, 2009. Again, I want to stress out that most of the questions here are modified from its original form for the purpose of improving the question. 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 C.198 HP               D. 202 HP P = (D3N )/38 -- for mula for short shafts from PSME code P = (4)3(120)/38 P= 202 HP Past Mechanical Engineering Board Exam Question Number 2 An instrument that measures the hardness of the work piece in terms of elasticity. a. Durometer b. Scleroscope c. Mohs's Scale d. Brinell Tester Source: Machinery’s Handbook

### SOLUTION TO MECHANICAL BOARD EXAM PROBLEMS: Power Set-1

Here are the solutions to board problems given at Power Subject Set-1. If you do not understand anything, feel free to write a comment voicing out your concern. I'm still looking for better ways to present my solution. I still don't know how to present equations and mathematical symbols with blogger. Please bear with me. 1. An automobile tire is inflated to 32psig pressure at 50 degree F. After being driven, the temperature rises to 75 degree F. Determine the final gage pressure assuming the volume remains constant. (Electrical Engineering Board Exam Problem) Solution: Since volume is constant, use Charles’ Law on constant volume processes. P1/T1=P2/T2 Note: P and T should be absolute. (32+14.7)/ (50+460) =P2/ (75+460) P2=48.99 psia Converting back to gage pressure, P2g=48.99-14.7 P2g=34.29 psig 2. Four hundred cubic centimeters of gas at a pressure of 740 mmHg absolute and temperature of 18 degree C undergoes a process until the pressure and temperature be

### BOARD EXAM TIP: Which Review Center?

First of all, I would like to apologize for a long time I haven't posted anything but introduction. The reason for that is I'm busy optimizing the design of this site. I'm hoping that the make over is good. Anyway, I would like to dedicate this article to those who are going to take/retake the board exam this coming October. My sincere wish that you bring out the best among yourselves and may the deserving ones pass the exam. Going back to the One-Million-Peso worth question: "Which review center should I enroll?" , I would like to answer that in the most unbiased way I can. Of course, I'm only human and I had also my preferences but I will try my best to hide it. To start with I will enumerate some of the prominent review centers that offer board exam reviews for mechanical engineering in the Philippines. 1. Alcorcon (Cebu & Manila) 2. Excel (Cebu & Manila) 3. Linx Engineering (Manila) 4. MERIT (Manila) 5. PRIME (Cebu) 6. RLB's