Deck 9: Waves

Question 1

The period of wind waves is usually expressed in:

A) feet or meters.
B) miles per hour, or kilometers per hour.
C) seconds.
D) feet or meters per hour.

Answer 1

C

Question 2

Constructive Interference in waves can cause:

A) an occasional wave greater than any noted before or after its occurrence.
B) every other wave to be larger or smaller than those preceding or following.
C) waves to get smaller within 24 hours.
D) waves to double in height every 24 hours.

Answer 2

A

Question 3

The Ramapo wave is unique because:

A) many lives were lost when it struck the shore.
B) it is the largest wave ever observed by people.
C) it is the largest wave accurately measured by direct observation.
D) it was captured alive and brought to the Woods Hole Oceanographic Institution in 1933 where it is presently on display. Tickets are hard to obtain.

Answer 3

C

Question 4

The distance measured from trough to trough of a wave is:

A) the wavelength.
B) the wave height.
C) the wave period.
D) the orbit.

Question 5

Water particles in a deep-water wave:

A) move rapidly toward the shore.
B) move in circular orbits.
C) do not move; only the wave form moves.
D) move in flat elliptical circles.

Question 6

What wave form typically carries the greatest amount of energy through the ocean surface at any given time?

A) wind waves
B) tsunami
C) seiches
D) tides

Question 7

When waves approach the shore, a series of changes takes place. One change is that the:

A) wave crest forms a steep peak.
B) wavelength increases.
C) wave height decreases.
D) wave velocity increases.

Question 8

The diameter of the orbits of water particles in a deep-water wave is equal to the:

A) wavelength.
B) wave period.
C) wave velocity.
D) wave height.

Question 9

Waves at the shore will start to break when the:

A) water depth is about twice the wavelength.
B) crest flattens into a rounded form.
C) wave period increases to 15 seconds.
D) water depth is about four-thirds the wave height.

Question 10

The ultimate height of a wind wave will depend on:

A) the fetch.
B) the length of time the wind blows.
C) the velocity of the wind.
D) all of these

Question 11

As the wind velocity increases during a storm:

A) the wave height increases.
B) the wave velocity decreases.
C) the wind tends to flatten the ocean surface.
D) mass transport decreases in the open ocean.

Question 12

Near shore, if the wave crests are 200 feet apart, the wave will "feel" bottom when the depth is about:

A) 20 feet.
B) 50 feet.
C) 100 feet.
D) 200 feet.

Question 13

Waves tend to be parallel to the shore when they break due to the process of:

A) diffraction.
B) reflection.
C) refraction.
D) reaction.

Question 14

Which of these lists is arranged in order from smallest wavelength to longest wavelength?

A) seiches, tsunami, wind waves, tides
B) wind waves, seiches, tsunami, tides
C) wind waves, tsunami, seiches, tides
D) tides, seiches, tsunami, wind waves

Question 15

As wind waves move out of a storm area:

A) the short waves move out first and form "chop."
B) the short-period waves overtake the long-period waves.
C) the waves are sorted by velocity and form the swell.
D) the sea becomes flat outside the storm area.

Question 16

Rogue waves are best described as:

A) the highest waves of a tsunami.
B) a breaking internal wave.
C) a strong rocking motion within a harbor.
D) a single massive wave that develops in the open ocean.

Question 17

Waves with the greatest propagation rate or celerity:

A) have the longest wavelengths.
B) occur in shallow water only.
C) form when the wind is blowing less than 0.5 nautical miles per hour.
D) have wave periods of less than one second.

Question 18

In shallow water, the motion of water particles:

A) ceases completely.
B) forms large circular orbits.
C) becomes a back-and-forth motion near the bottom.
D) becomes an up-and-down motion near the bottom.

Question 19

The first waves to form on the ocean surface when the wind starts to blow are:

A) gravity waves.
B) internal waves.
C) swell.
D) capillary waves.

Question 20

Unlike other moving things, wind waves travel over great distances in virtually straight lines. This is physically possible because:

A) while the wave is moving, some water molecules are traveling in closed circles.
B) the waves don't move as fast as speeding cannon balls, so the Coriolis effect has no influence on them.
C) waves carry only energy, and energy has no mass, and is therefore not subject to Coriolis deflection.
D) waves curve one way in the southern hemisphere and the other way in the northern hemisphere. Waves only look like they are coming in a straight line from their point of origin. It's all a gigantic optical illusion, actually.

Question 21

Classification of waves depends on:

A) depth and trough.
B) wave height and wavelength.
C) depth and wave height.
D) wavelength and depth.

Question 22

Celerity is a measure of wavelength and the units are meters.

Question 23

Internal waves commonly form at the base of the pycnocline.

Question 24

The best place to study the effects of a seiche is:

A) on a shallow beach at the edge of the Pacific.
B) in a harbor or lake.
C) near tropical islands in the Pacific or Atlantic.
D) in the open sea.

Question 25

In the open sea, tsunami:

A) are giant breaking waves that are dangerous to ships.
B) are slow-moving waves, slower than the swell.
C) are long-period waves, often of 5-20 minutes.
D) have short wavelengths of 100-200 feet, similar to wind waves.

Question 26

In the open sea, tsunami reach an average wave height of about:

A) 1 meter.
B) 10 meters.
C) 100 meters.
D) 1,000 meters.

Question 27

Swell is the result of wave separation or dispersion.

Question 28

Tsunami or seismic sea waves are generated by:

A) storms at sea.
B) tidal currents in the open sea.
C) breaking internal waves.
D) coastal or submarine earthquakes.

Question 29

For a wave, the longer the wavelength, the faster the wave energy will move through the water.

Question 30

The energy that causes ocean waves to form is called a disturbing force.

Question 31

The wavelength of a wave is a measure of the highest part of the wave above the average water level.

Question 32

A tsunami is a shallow water wave that moves at high speeds.

Question 33

The greatest disturbing force creating waves is:

A) convection.
B) wind.
C) gravity.
D) heat.

Question 34

A seiche is a short wave found in areas of the ocean farthest away from the continents.

Question 35

A ___________ is a gravity wave formed by the transfer of wind energy over the water.

A) swell
B) capillary wave
C) wind wave
D) tsunami

Question 36

Which of the following statements is FALSE concerning capillary waves?

A) Capillary waves can be important because they mix nutrients into surface waters.
B) Capillary waves are the source of wind waves.
C) Capillary waves form as friction stretches the water surface.
D) Capillary waves form small ripples on the surface.

Question 37

When a tsunami reaches shore,

A) the wave height is increased by entry into shallow water.
B) it always arrives at the time of a high tide.
C) the wave will appear as a single huge breaking wave.
D) it will always race hundreds of meters inland.

Question 38

The uninterrupted distance over which the wind blows without change in direction is the:

A) fetch.
B) wavelength.
C) wind length.
D) wind cell.

Question 39

A wave first begins to break against the shore when the ratio of wave height to water depth is about 3:4.

Question 40

Wave reflection causes interference in the form of vertical oscillations that are called standing waves.

Question 41

Describe how a tsunami is formed and how it can travel great distances at great speeds.

Question 42

Describe how a wave breaks on the shore as it transitions from a deep-water wave to a shallow-water wave.

Question 43

What is the relationship between the wave crest, trough, height and wavelength?

Question 44

What is a storm surge and how does it differ from a breaking wind wave?

Question 45

What is fetch and how does it influence wind wave development?