Waves

Question 1

High Frequency, Short Wave

Answer 1

Ripple

Question 2

Distance to complete one complete wave (sine) cycle, defined as 2π radians

Answer 2

Period T

Question 3

Low frequency, long wave and high frequency waves dissipated

Answer 3

Swell

Question 4

Stable wave with maximized wave height and energy

Answer 4

Fully developed wave

Question 5

A wave pattern in the typical sine pattern

Answer 5

Sinusoidal Waves

Question 6

1 second =

Answer 6

9.43 radians

Question 7

If spring is compressed or placed in tension, force that will try to return to its original location is

Answer 7

Restoring Forve

Question 8

The number of radians completed in 1 second

Answer 8

Frequency

Question 9

π =
2π =

Answer 9

180 deg, 360 deg/ 1 complete cycle

Question 10

The magnitude of the restoring force is proportional to the magnitude of the displacement

Answer 10

Linear Force

Question 11

The distance travelled at a given time T

Answer 11

Displacement (Z)

Question 12

Exiting force or waves

Answer 12

Motion Source

Question 13

Radiated Wave, eddy and viscous force

Answer 13

Damping Source

Question 14

Unless energy is continually added, the system will eventually come at rest

Answer 14

Force function and Resonance

Question 15

When the force function is applied at the same frequency as the oscillating system, a condition of — exists

Answer 15

Resonance

Question 16

Condition 1: the frequency of the forcing function is much smaller than the system

Answer 16

Z=F/k

Question 17

Condition 2: The frequency of the force function is much greater than the system

Answer 17

Z=0

Question 18

Condition 3: The frequency of the forcing function equals the system

Answer 18

z = Infinity (Resonance)

Question 19

Translational Motion

Answer 19

Surge, Sway, Heave

Question 20

Simple Harmonic Motion

Answer 20

Heave Pitch and Roll

Question 20

Rotational Motion

Answer 20

Roll, Pitch, Yaw

Question 21

Stiff Ship, small period; bad seakeeping quality

Answer 21

Large GM

Question 22

Tender Ship, less stable; good seakeeping quality

Answer 22

Small GM

Question 23

Encounter Frequency = Natural Frequency

Answer 23

Resonance

Question 24

Are well Damped due to large wave generation

Answer 24

Heave and Pitch

Question 25

Susceptible to encounter frequency and ---- are not damped well due to small damping

Answer 25

Roll Amplitude, roll motions

Question 25

Caused by relative motion of ship and sea

Answer 25

Non-Oscillatory Dynamic Response

Question 26

More likely to occur with roll than pitch and heave

Answer 26

Resonance

Question 27

opposite case of shipping water where the bow of the ship is left unsupported

Answer 27

Forefoot Emergence

Question 27

Caused by bow submergence

Answer 27

Shipping Water

Question 28

Impact of the bow region when bow reenters into the sea. Causing severe structural Vibration

Answer 28

Slamming

Question 29

The stern version of forefoot emergence

Answer 29

Racing

Question 30

cause the propeller to leave the water and thus cause the whole ship power to race

Answer 30

severe torsion and wear in shaft

Question 31

The effects of all these response is to increase the resistance

Answer 31

Added Power

Question 32

limits Awl and TPI reducing heave acceleration

Answer 32

Volume is distributed higher

Question 32

Limits MT1 reducing pitch acceleration

Answer 32

forward and aft are V-shaped

Question 33

Very common passive anti rolling device Located at the bilge turn Reduce roll amplitude up to 35%

Answer 33

Bilge Keel

Question 33

limits the Ixx reducing the stiffness of GZ curve thereby reducing roll acceleration

Answer 33

Wider water plane forward

Question 34

Reduce the roll motion by throttling the fluid in the tank relative change of G of fluid will dampen the roll

Answer 34

Tank Stabilizer

Question 35

Very Common active anti-rolling device Located at the Bilge Keel Controls the roll by creating lifting force

Answer 35

Fin Stabilizer

Question 36

A ship heading directly into the waves will meet the successive waves much more quickly and the waves will appear to be a much shorter period

Answer 36

Head Sea

Question 37

A ship moving in a following sea, the waves will appear to have a longer period

Answer 37

Following Sea

Question 38

If wave approaches a moving ship from the broadside there will be no difference between wave period and apparent period experienced by the ship

Answer 38

Beam Sea

Question 40

Are periodic, uniform waves with a consistent wavelength and amplitude They repeat at regular intervals, making them idealized representations of wave motion

Answer 40

Regular Waves

Question 41

are more common in nature and represents complex combination of different wave frequencies, amplitudes and directions. They vary significantly over time.

Answer 41

Irregular Waves