Maritime Engineering Exam Ethiopia

Bahir Dar University Ethiopian Maritime Training Institute

SCREENING TEST FOR ADMISSION TO PRE-SEA TRAINING – Six months training scheme INSTRUCTIONS TO CANDIDATES: Read the following instructions carefully before answering

1. Check the box of the most correct answer for each question. Separate papers will not be provided. If you change your mind, strike through the wrong answer and check another. 2. Ensure to enter your name and reference/register number in the space provided for the same. 3. Any candidate found indulging in any malpractice will be debarred from the test and will not be considered for admission. 4. Mobile Phones are prohibited in the Examination Hall. 5. You may Use scientific calculator only.

Name of Candidate (in block letters) ______________________ ____________________________________ ______________

Reference Number:

Signature: ____________________

Section A B C D E

Date: __________________

Subject

Mark

Mathematics Industrial Chemistry Basic Engineering & Mechanical Science Thermodynamics Electrical Engineering

Total Mark: Mark:

0

Name of Examiner: ______________________

Signature of Examiner: __________________ Date: ______________

Group 1

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Bahir Dar University Ethiopian Maritime Training Institute

SECTION - A

Mathematics (4 x 5 = 20 points)

1.

The solutions to the following equation are:

log 3 ( x

a)  x1 = 5 , x2 = 3

b)  x1 = 6 , x2 = 3

c)  x1 = 4.5 , x2 = 2

d)  x1 = 6 , x2 = 2

2.

b) 6 , − 6

+ 9) − log 3 ( x − 1) = 2

2 2 x

The solutions to the following equation are: a) 3 , − 3

2

− 9 x = 18

c) 1.5 , − 3

d) 1.5 , − 6

3. The sum of two positive numbers is 24. which numbers will give the maximum result, if one of them will be multiplied with the square of the other:

a)

8;16

b) 9;15

c) 10;14

d) 12;12

4. The shaded area in the following drawing is: a)

9

b)

4.5

c)

13.5

d)

18

 y 2

=

9 − x2

5. ABCDA'B'C'D' is a rectangle box with a square basis. The diagonal BD' is twice the size of the side of the basis. The angle between the diagonal BD' and the basis ABCD is: a)

37.5°

b)

60°

c)

45°

d)

30°

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Bahir Dar University Ethiopian Maritime Training Institute SECTION - B

Industrial Chemistry (4 x 5 = 20 points)

1.

When salt water is allowed to evaporate in an open container, what happens to the concentration of salt in the water?

2.

a)

It remains constant throughout the process.

b)

It increases or decreases depending on the temperature of the water.

c)

It decreases.

d)

It increases.

Which of the following is a correct statement?

3.

a)

A solution of an element is an electrolyte.

b)

Solutions of all acids and basics conduct electricity equally well.

c)

A solution of a soluble ionic compound is an electrolyte.

d)

Ethanol, C2H5OH, is a strong electrolyte.

Choose the aqueous solutions with the lowest PH:

4.

a)

Nitric acid , HNO 3 , 0.1M

b)

Acetic acid , CH 3 COOH , O.4M

c)

Sulfuric acid , H 2SO4 , 0.1M

d)

Carbonic acid , H 2CO3 , 0.2M

What mass of NaOH (s) is required to react exactly with 25 ml of 0.3M H 2SO4 (aq)?

0.6  gr 

a)

5.

b)

2.4 gr 

c)

0.3 gr 

d) 1.2  gr 

Which of the following statements about corrosion is not correct? a)

Atmospheric corrosion of iron occurs very slowly in dry air, but more rapidly in the presence of moisture.

b)

Iron rusts more quickly in contact with a less active metal (such as Cu) and slower in contact with a more active metal (such as Mg)

c)

Iron rusts more quickly at high OH ions concentration.

d)

Iron does not rust in air-free water, oxygen must be present.

-

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Bahir Dar University Ethiopian Maritime Training Institute SECTION - C

Basic Engineering & Mechanical Science (4 x 5 = 20 points)

A ship is sailing due east at 18 knots runs into a 3 knot  current moving 40 East of North. 

1.

The resultant speed an direction of the ship are:

2.

a)

20.3 knots ; 6 30' N to E  

b)

15.82 knots ; 8 35' N to E  

c)

20.06 knots ; 6 35' N to E  

d)

20.06 knots ; 83 24' N to E  









A wheel and axle is carried in horizontal bearings (see sketch). When the load is allowed to fall from rest, it falls 3 m in 8 seconds. If the diameter of the axle is 50 mm, The linear 2

2

acceleration of the load (in m/s  ) and the angular acceleration of the wheel (in rad/s  )are: 2

a)

0.09375 m s ; 3.75 rad s

b)

0.1875 m s ; 7.5 rad s

c)

0.0468 m s ;1.875 rad s

d)

0.1405 m s ; 5.625 rad s

2

2

2

2

2

2

2

3. A 3 kg hammer head moving at a velocity of 7 m/s strikes the head of a wedge and is brought to rest in 1/100 s. The average force of the blow is:

a)

21 kN 

b)

2.1 kN 

c)

210  N 

d)

20.6 kN 

4. The stiffness of a spring is 88  N/mm of axial compression. The work to increase the compression from 50 mm to 80 mm is: a) 132  J 

Group 1

b)

211.2  J 

c) 171.6  J 

d) 17.5 J 

Page 4 of 7

Bahir Dar University Ethiopian Maritime Training Institute 2

5. A tie bar is made of mild steel of tensile strength 462  MN/m  is to carry a tensile load of 11.12 kN . The minimum diameter of the bar allowing a factor of safety of 12, is:

a) 17 mm

b)

230 mm

c) 188 mm

d) 19.17 mm

SECTION - D

Thermodynamics (4 x 5 = 20 points)

The temperature inside a refrigerated cold chamber is −3 F  when the outside temperature is 

1.

−60



F  . The temperature difference between inside and outside in degrees Celsius is:

a) 33.3  C  

2.

b) 35 C 

c) 63  C 





d) 36.3  C  

A casting of mass 5 kg is pulled a distance of 10 m along a horizontal floor, the coefficient of friction between the surfaces of the casting and floor being 0.4. The heat generated is: a) 19.62 J 

200 J 

b)

2.5 kg of brass of specific heat 0.39 kJ 

3.

c) 196.2 J 

d) 20 J 

 at a temperature of 176 C  is dropped into 

kgK 

1.2 liters of water at 14 C . The resultant temperature of the mixture is: 

a) 19.62 J 

b) 200 J 

c) 196.2 J 

d) 20 J 

3 A solid cast iron sphere is 150 mm diameter, density = 7.21 g/cm , Specific heat = 0.54

4.

-5

kJ/kgK , coefficient of linear expansion = 1.12 x 10  / °C . If 2110 kJ  of heat is transferred to

it, the increase in diameter is:

a)

0.0566 mm

Group 1

b) 0.46 mm

c)

0.6661mm

d) 0.5152 mm

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Bahir Dar University Ethiopian Maritime Training Institute

3

0.25 m  of a gas at 21 C   is heated at constant pressure to a temperature of 315 C . The

5.





final volume is:

a)

0.5 m

3

b) 3.75 m

3

c) 1.08 m

3

d) 3.75 m

3

SECTION - E

Electrical Engineering (4 x 5 = 20 points)

1.

The total current in the following circuit is:

a) 1.14 A

2.

c)

0.96 A

d) 6.0 A

The reading on the Voltmeter in the following circuit is:

a) 180 V 

3.

b) 6.23  A

b) 30 V 

c)

60 V 

d) 96 V 

A battery consists of 4 cells in series, each of e.m.f 1.5 V and internal resistance 0.6 battery is connected to two resistors of 2

Ω and

Ω.

If the

0.6 Ω which are connected in series. The

circuit current is:

a) 1.2

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b) 13 A

c)

2.3 A

d)

2.5  A Page 6 of 7

Bahir Dar University Ethiopian Maritime Training Institute

4.

A 220 V diesel-driven generator is required to supply the following on full load: a) Lighting one hundred 100 W and two hundred 60 W lamps, b) a heating load of 25 kW, c) Miscellaneous small loads taking a total current of 30 A. If the generators efficiency is 85%, the required power output of the diesel engine is:

a)

5.

53.6 kW 

b)

45 kW 

c)

53 kW 

d) 63.1 kW 

An iron-cored coil of 2000 turns produced a magnetic flux of 30 mWb when a current of 10 A is flowing from the D.C. supply. If the time of opening the supply switch is 0.12 seconds and the residual flux of the iron is 2 mWb, the average value of the induced e.m.f. is:

a)

500 V 

Group 1

b)

466.6 V 

c)

46.66 V 

d) 50 V 

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