Deck 9: The Tides

Question 1

Earth and the moon rotate around their common ________.

Answer 1

center of mass

Question 2

If the tidal current is maximum at midtide level, the tide is a progressive wave type.

Answer 2

False

Question 3

The shape and depth of the ocean basins control the progression of the tide wave.

Answer 3

True

Question 4

Tides arrive at the same location at the same time each day.

Question 5

The sun plays a greater role in producing the tides than the moon.

Question 6

The values of tide corange lines decrease as they move away from the amphidromic point.

Question 7

The tide wave that progresses across the oceans at low latitudes is forced by the tide-raising force to travel at a speed greater than its natural speed.

Question 8

A Northern Hemisphere ocean basin with a standing-type tidal oscillation will have a standing wave that rotates counterclockwise.

Question 9

Tidal power is periodic, but it is always available at about the same time each day.

Question 10

Any local tide can be predicted from astronomical data alone.

Question 11

The angle between Earth's equatorial plane and the moon's orbital plane is called the moon's ________.

Question 12

A tidal pattern of two high tides and two low tides each day is known as a diurnal tidal pattern.

Question 13

The co-range lines of a rotary standing tide wave all converge at the ________ point.

Question 14

The time required to complete the tidal sequence of a solar tide is equal to the time period needed to complete the sequence of a lunar tide.

Question 15

Tides are deep water waves.

Question 16

Spring tides are present when the lunar and solar tide waves are in phase with each other.

Question 17

The tidal bulge on the side of the earth facing the tide-raising body is caused by the difference between the tidal force at the surface of the earth and the tidal force at the earth's center.

Question 18

Hawaii is near an amphidromic point; therefore, its tidal range is small.

Question 19

The time period between successive new moons is 29.5 days.

Question 20

Neap tides occur during a full moon.

Question 21

A rising tide is known as an ebb tide.

Question 22

Tidal waves are deep water waves.

Question 23

The antinode of a rotary current is the amphidromic point.

Question 24

A region of mixed tides tends to have more diurnal type tides if the semidiurnal component of the tide-producing force weakens.

Question 25

The greatest tidal range occurs farthest from the amphidromic point.

Question 26

Rotary currents progress in a clockwise direction in the northern hemisphere.

Question 27

___ tides occur at the first quarter moon.

A) Mixed
B) Diurnal
C) Semidiurnal
D) Neap
E) Spring

Question 28

The ________ tide component tends to make high tides appear about one hour later each day.

A) diurnal
B) semidiurnal
C) lunar
D) solar
E) declinational

Question 29

If the tide-producing force is proportional to G × M/R³, then the moon exerts a greater tide-raising force than the sun due to the difference in their masses rather than a difference in their distances from the earth.

Question 30

The combination of diurnal and semidiurnal tides produces a ______ tide.

A) diurnal
B) semidiurnal
C) mixed semidiurnal
D) standing
E) equilibrium

Question 31

Diurnal tide cycles occur

A) once a day.
B) twice a day.
C) three times a day.
D) only at low latitudes.
E) only at high latitudes.

Question 32

To navigate swift tidal currents safely, small boats need to wait for

A) high water.
B) low water.
C) slack water.
D) ebb tide.
E) flood tide.

Question 33

Using equilibrium tidal theory, the tide may be considered a wave with a wavelength approximately

A) the diameter of Earth.
B) half the diameter of Earth.
C) the circumference of Earth.
D) half the circumference of Earth.
E) the radius of Earth.

Question 34

The length of a tidal day for a mixed semidiurnal tide is ________ hours.

A) 12
B) 12.4
C) 24
D) 24.8
E) 48

Question 35

The terms ebb and flood pertain to

A) low and high water stands.
B) outgoing and incoming tides.
C) the direction of the tidal current flow.
D) outgoing and incoming tides and the direction of the tidal current flow.
E) low and high water stands, outgoing and incoming tides, and the direction of the tidal current flow.

Question 36

Lunar tides are larger than solar tides.

Question 37

Open ocean tides can be monitored and recorded from satellites.

Question 38

The typical semidiurnal period of a solar tide according to equilibrium tidal theory is ______ hours, whereas the semidiurnal lunar tidal period is _______ hours.

A) 12.0; 12.4
B) 24.0; 24.8
C) 12.4; 12.0
D) 12.8; 24.0
E) 12.0; 12.0

Question 39

The center of mass of the Earth-moon system

A) lies beneath Earth's surface on a line that joins the centers of Earth and the moon.
B) describes the true orbit of the Earth-moon system about the sun.
C) is between Earth and the moon on the line through their centers.
D) lies beneath Earth's surface on a line that joins the centers of Earth and the moon and describes the true orbit of the Earth-moon system about the sun.
E) lies beneath Earth's surface on a line that joins the centers of Earth and the moon, describes the true orbit of the Earth-moon system about the sun, and is between Earth and the moon on the line through their centers.

Question 40

Diurnal tides are more prevalent at middle latitudes when the tide-raising bodies are

A) at low declination.
B) at high declination.
C) in line with each other.
D) 90 degrees to each other.
E) 180 degrees to each other.

Question 41

An ocean basin can have a natural period of oscillation that matches the tidal day if the basin depth is _______ and its length and width are ______.

A) large; small
B) large; large
C) small; large
D) small; small
E) large; large and small; small

Question 42

Tidal currents in the open ocean are

A) rotary currents.
B) formed by the passing tide wave.
C) deflected by the Coriolis effect.
D) present at all depths.
E) All of these are correct.

Question 43

Real tides in ocean basins feel the effect of the

A) Coriolis effect.
B) continents.
C) water depth.
D) ocean basin's standing wave.
E) All of these are correct.

Question 44

Tides

A) are shallow water waves.
B) are progressive waves.
C) rotate in ocean basins.
D) have elliptical water particle orbits.
E) All of these are correct.

Question 45

Tides of large amplitude occurring every two weeks at the new and full moon are called _______ tides.

A) equatorial
B) neap
C) spring
D) declinational
E) semidiurnal

Question 46

The tidal current in a narrow tidal channel is likely to

A) have a distinct rotary component.
B) be unidirectional at all times.
C) change direction as the tides change.
D) be nonrotary.
E) change direction as the tides change and be nonrotary.

Question 47

The tidal range toward the center of an ocean basin with a rotary standing tide is _______ the range at the edges of the basin.

A) smaller than
B) larger than
C) about the same as
D) of longer duration than
E) None of these are correct.

Question 48

A tidal day is

A) 12 hours.
B) 12 hours and 25 minutes.
C) 24 hours.
D) 24 hours and 50 minutes.
E) It depends on the day.

Question 49

Some oceanic basins promote rotary standing tide waves. In the Northern Hemisphere, the tide wave rotates __________ and the tidal current rotates _______.

A) counterclockwise; clockwise
B) counterclockwise; counterclockwise
C) clockwise; counterclockwise
D) clockwise; clockwise
E) clockwise; the current does not rotate

Question 50

A spring tide occurs approximately

A) once per week.
B) every two weeks.
C) once per month.
D) once per year.
E) twice per year.

Question 51

Friction between the moving tide wave and the turning Earth acts to

A) slow the rotation rate of Earth and make the tide wave move as a forced wave.
B) increase the free wave speed of the tide wave.
C) make no difference to Earth's rotation and wave speed.
D) All of the answers are correct.

Question 52

If a narrow coastal basin oscillates with a period that nearly matches the tidal period, near its entrance the basin has _______ amplitude tides and ________ tidal currents.

A) large; small
B) small; small
C) large; large
D) small; large
E) no change in; no change in

Question 53

Tidal days are longer than solar days because

A) the moon rotates more slowly than the Earth.
B) the moon rotates more quickly than the Earth.
C) the moon moves in the same direction around the Earth as the Earth revolves on its axis.
D) the moon moves in the rotates in the opposite direction of the Earth.
E) tidal days are not longer than solar days.

Question 54

Which factor has the greatest tide generating effect?

A) Mass of the Earth
B) Mass of the tide generating body
C) Speed of rotation
D) Distance between the Earth and tide generating body
E) Mass of the tide generating body and speed of rotation

Question 55

Tidal currents

A) move water with the ebb tide.
B) move water with the flood tide.
C) can be swift and dangerous.
D) move water with the ebb tide, move water with the flood tide, and can be swift and dangerous.
E) Tides do not produce currents.

Question 56

Since the earth turns _______ the tide wave tends to move _______ around Earth.

A) eastward; westward
B) eastward; eastward
C) westward; eastward
D) westward; westward
E) northward; southward

Question 57

When will tidal range be greatest?

A) Spring tide in July
B) Spring tide in January
C) Neap tide in July
D) Neap tide in January
E) Spring tide in July and spring tide in January

Question 58

Tide waves have

A) crests at the high-water level and troughs at the low-water level.
B) periods of 24 hours and 50 minutes or 12 hours and 25 minutes.
C) speeds that are constant.
D) crests at the high-water level and troughs at the low-water level, periods of 24 hours and 50 minutes or 12 hours and 25 minutes, and speeds that are constant.
E) crests at the high-water level and troughs at the low-water level and periods of 24 hours and 50 minutes or 12 hours and 25 minutes.

Question 59

If the HHW tide occurs at 1400 hours on day 1, at what time does the next HHW occur?

A) 2012 hours on day 1
B) 0225 hours on day 2
C) 1837 hours on day 2
D) 1400 hours on day 2
E) 1450 hours on day 2

Question 60

In an open-ended embayment connected to the sea (for example, the Bay of Fundy), how much of the fundamental standing tide wave form is present?

A) One-half the wave
B) The complete wave
C) One-quarter the wave
D) Two waves
E) Four waves

Question 61

Energy can be extracted from tides by

A) the rise and fall of the water.
B) the horizontal movement of water in tidal currents.
C) the declination of the tides.
D) only from diurnal tides.
E) the rise and fall of the water and the horizontal movement of water in tidal currents.

Question 62

The possibility of obtaining large amounts of energy from the tides exists where

A) there are large tidal ranges.
B) there are small tidal ranges.
C) there are narrow channels with swift tidal currents.
D) there are wide channels and slow tidal currents.
E) there are large tidal ranges and there are narrow channels with swift tidal currents.