Certification Assistance for Marine Engineers

Brought to you by www.dieselduck.net comments to webmaster@dieselduck.net
Transport Canada has ask us to advise users of this webpage to keep in mind that these questions are not the exact questions found in their exams. Martin's Marine Engineering Page - www.dieselduck.net is not affiliated with Transport Canada and these questions have been gathered from various sources.

As I come across more questions, I will post them - if you have some, submit here.

Martin

A visitor writes in, after his exam in 2008, the following...

I just wrote the third class electro and would like to pass on some questions I had. I found that most of them were not really in the syllabus.

1. Describe how to find the unknown resistance with the Wheatstone bridge. Sketch as well.

2. Explain the workings with the aid of a circuit diagram a earth-ground fault on a DC system.

3. Describe in detail a storage cell including construction.

4. Sketch and describe a circuit breaker and explain some of the safety features.

5. Describe an alternator of any type and explain what is meant by 1) force lines 2) induction 3)? 4)? I forget. and briefly describe the right hand rule.

6. I forget the exact example but it gave a resistance for a precise of wire at 0ºC and increased the temp to 50ºC and you had to figure out the new resistance. I can submit a same type question if you like when I get my books back.

7. Something about a diodes and vacuum tube

8. At what speed would a synchronous motor run... Explain

9. Explain the relation of resistance with a conductor and an insulator.

1. What is a Wattmeter? Describe, with aid of sketch, the internal construction of a Wattmeter.

2. State the advantages of the alternating current generators over the direct current generators.

3. Describe, with aid of sketch, the essential parts of a typical gas engine ignition system.

4. A wire is cutting magnetic lines of force at the rate of 200,000,000 lines per second. What average voltage is induced across the terminals of the wire?

5. Describe the construction of lead storage cell. Give the chemical action produced in the cell on discharge.

6. A cell whose internal resistance is 0.16 ohm is delivering 0.5 amp. The external resistance is 2.8 ohms. Find:
a) Volts used in overcoming the internal resistance
b) Terminal voltage
c) Electromotive force (E.M.F.)

7. Explain the effects of temperature on resistance of the following conductors:
a) aluminum,
b) manganin,
c) liquid,
d) carbon.

8. The resistance of a round conductor is 0.5 ohm. Its cross-sectional area is 0.78 square inch. What would be the resistance if the cross-sectional area were 3.12 square inches.

9. The brush potential of a generator is 110 volts. The total line resistance is 6 ohms. How much extra line resistance is necessary to limit the current flow to 10 amperes?