Test 1

Question 1

Length to beam ratio

Answer 1

L/B

Question 2

Which ship turns more easily?

Answer 2

Wider beam

Question 3

Block coefficient (coefficient of fineness) is equal to the

Answer 3

Ratio of the hull volume/ the cuboid containing it

V/ lxbxte

Question 4

The higher the block coefficient

Answer 4

The harder it is to maneuver the ship

Question 5

Bernoulli’s principle

Answer 5

Higher speed = lower pressure

Lower speed = higher pressure

Question 6

Lift contributes to ?% of the propulsive action of the prop?

Answer 6

30-50%

Question 7

A narrow ship easily maintains

Answer 7

It’s heading

Question 8

Block coefficient can vary from

Answer 8

0.5 for a fast naval ship to about 0.85 for a VLCC

Question 9

A propeller creates a propulsive force of about

Answer 9

One ton per 100 hp

Question 10

The first successful steamship driven by screw propulsion to operate on the oceans was the

Answer 10

SS Archimedes

Question 11

How does Bernoulli’s principle affect the operation of a propeller?

Answer 11

Lift is generated on the low pressure side of the blades

Question 12

What is newtons third law?

Answer 12

Every action has an equal and opposite reaction

Question 13

Newtons first

Answer 13

Object at rest will remain at rest unless acted on by an unbalanced force

Question 14

Newtons second

Answer 14

Acceleration is produced when a force acts on a mass

Question 15

What causes the Stern to move to port and provide hull wash on the starboard side when the engines are astern?

Answer 15

Deadwood effect

Question 16

The greater the blade area ratio

Answer 16

The less vibration and noise

Question 17

Grader blade area ratio affects

Answer 17

Drag and reduces efficiency

Question 18

Where is cavitation most likely to appear?

Answer 18

The blade tips and leading edge

Question 19

Is aeration the same as cavitation?

Answer 19

No

Question 20

Are controllable pitch and variable pitch propellers the same?

Answer 20

Yes

Question 21

Two equal ships except one has a fixed pitch and the other has a controllable pitch. They’re traveling in a straight line and they both stopped or propulsion. Which will respond better?

Answer 21

The ship with a fixed pitch propeller because it is still allowing water over the rudder and the controllable does not

Question 22

A broad ship will stop turning when the rudder is returned to midship

Answer 22

False

Question 23

Which ship has a wider turning diameter, a broad beam or a narrow beam?

Answer 23

Narrow beam

Question 24

Are controllable pitch propellers more efficient than fixed pitch propellers going to Stern?

Answer 24

No

Question 25

The ratio of the rudder blade to the underwater area of the hull varies from

Answer 25

1.5-5%

Question 26

A rudder is limited to a range of about what angle?

Answer 26

35 | Because the rudder can stall

Question 27

Which rudder has two pieces coming off the stem posts that are separate from each other?

Answer 27

Balanced

Question 28

The first element in design of a rudder is the

Answer 28

Surface area

Question 29

What are the two types of high-performance rudders in the modern merchant marine fleet?

Answer 29

``` Becker rudder (flap rudder) Schilling rudder ```

Question 30

What’s the main disadvantage of a Kort nozzle

Answer 30

In speeds greater than 12 kn drag is significantly increased

Question 31

What kind of rudder loses effectiveness at angles greater than 10°?

Answer 31

Balanced spade

Question 32

The old type of rudder mounted with the prop

Answer 32

Contra guide

Question 33

What is the penalty for a large rudder?

Answer 33

Drag

Question 34

Why is a thruster propeller not the same design as a main propulsion propeller?

Answer 34

Because it only applies transversed thrust to port or starboard