Deck 10: Tides

Question 1

World-wide, the most common type of tides are:

A) semidiurnal.
B) mixed diurnal.
C) diurnal.
D) mixed node tides.

Answer 1

A

Question 2

Which of the following statements is FALSE concerning a lunar day?

A) A lunar day is shorter than a solar day.
B) A lunar day represents the time between when the moon is highest in the sky and the next time it is highest in the sky.
C) A lunar day is 24 hours 50 minutes.
D) Because of the length of a lunar day, lunar tides usually arrive 50 minutes later each day.

Answer 2

A

Question 3

The side of the Earth facing the moon will experience a high tide, while the opposite side of the Earth will have a:

A) low tide.
B) time of no tidal action.
C) high tide also.
D) tide that cannot be predicted.

Answer 3

C

Question 4

The longest of all ocean waves are called:

A) tsunami.
B) tides.
C) storm surge.
D) wind wave.

Question 5

When the sun and moon are in a line with the Earth, the:

A) gravitational attraction will be less.
B) difference between high and low tides will be minimal.
C) arrival of high tide will be delayed.
D) highest high and lowest low tides will occur.

Question 6

The tidal pattern characteristic of the west coast of the United States is:

A) mixed tides.
B) diurnal tides.
C) reversing tides.
D) amphidromic tides.

Question 7

A tide pattern of one high and one low each day describes a:

A) diurnal tide.
B) mixed tide.
C) solar tide.
D) semidiurnal tide.

Question 8

Which body has the greatest influence on ocean tides?

A) Sun
B) Moon
C) Jupiter
D) Venus

Question 9

Which of the following statements is FALSE concerning the equilibrium theory of tides?

A) The theory assumes that the seafloor does not influence tides.
B) The theory states that the surface of the ocean cannot conform to the combination of forces acting on it.
C) The theory presumes the surface of the ocean does conform to acting forces.
D) The theory states that there is a balance between all of the forces that influence the surface of the ocean including those that allow Earth to stay in stable orbit around the sun.

Question 10

The height of the ocean averaged over a few years' time is called:

A) mean high water.
B) mean low water.
C) tidal datum.
D) mean sea level.

Question 11

An amphidromic point is a:

A) no tide point in the ocean around which the tide crest rotates through one tidal cycle.
B) place in the ocean where tides are highest.
C) place in the ocean where tidal datum is displaced to the right (in the northern hemisphere), or to the south (in the southern hemisphere).
D) no tide point at the coast where there is a daily high tide, but no low tide.

Question 12

The reference level to which tidal height is compared is called the:

A) sea level of spring tides.
B) tidal datum.
C) maximum range.
D) tidal variance.

Question 13

Tractive forces:

A) are never responsible for the tides.
B) cause water to flow away from some ocean areas.
C) are the primary causes of tidal surges.
D) influence the atmosphere only.

Question 14

The only marine energy source being successfully exploited on a large scale is:

A) tidal power.
B) storm waves.
C) salinity differences.
D) thermal gradient.

Question 15

The rise and fall in sea level as a tide crest approaches and passes will cause a(n):

A) tidal bore.
B) tidal wave.
C) ebb current.
D) tidal current.

Question 16

Which of the following statements is FALSE concerning tides?

A) Because tides travel across the ocean, the crests and troughs that cause high and low tides are very large.
B) Tidal bulges are gravitational bulges that stay aligned with the moon or inertial bulges due to centrifugal force.
C) The combined forces of gravity and inertia result in tides.
D) The sun and the moon influence tides.

Question 17

The primary force(s) that cause(s) tides in the sea is (are):

A) coastal earthquakes and landslides.
B) wind and storms at sea.
C) the gravitational attraction of the moon and the sun.
D) the gravitational attraction of Mars and Venus.

Question 18

A steep wave moving upstream generated by the action of the tide crest in the enclosed area of a river mouth is called a:

A) tidal node.
B) tidal wave.
C) tidal surge.
D) tidal current.

Question 19

The time between high and low tide when the current changes direction is called:

A) ebb water.
B) flood tides.
C) slack water.
D) amphidromic points.

Question 20

Tidal bores usually occur:

A) in rivers or long narrow bays.
B) in open ocean far from land.
C) around islands.
D) in enclosed basins such as the Mediterranean.

Question 21

Slack water:

A) occurs at high tide.
B) occurs at low tide.
C) occurs when the current is changing direction.
D) occurs midway between high and low tide.

Question 22

The zero point on a tide graph is called the:

A) slack water point.
B) mean sea level point.
C) node point.
D) tidal datum.

Question 23

Most of the energy from the daily rise and fall of the tides comes from:

A) the rotation of the Earth.
B) winds.
C) heat.
D) the movement of plates.

Question 24

Tides caused by the inertia and the gravitational force of the sun and moon are called:

A) neap tides.
B) astronomical tides.
C) tidal surge.
D) meteorological tides.

Question 25

Tides are long waves that are generated by gravity and inertia.

Question 26

Which of the following is true about a tidal current?

A) The velocity of a tidal current increases with depth.
B) The velocity is always greater in the open ocean away from land.
C) The velocity of a tidal current decreases with depth.
D) They only approach shore during a storm surge.

Question 27

A low tide corresponds to the trough of the wave.

Question 28

A spring tide has a greater tidal range than a neap tide, and only occurs during the spring and summer months in each hemisphere.

Question 29

A tidal or lunar day is every 24 hours.

Question 30

Because of the combination of gravitational and inertial forces, tides are unpredictable.

Question 31

Which of the following statements best characterizes neap tides?

A) Neap tides occur when the moon, Earth and sun form a right angle.
B) Neap tides represent extreme tidal ranges.
C) Neap tides occur at the new and full moons every month.
D) Neap tides correspond with the timing of spring tides.

Question 32

A meteorological tide is caused by:

A) rogue waves.
B) storms.
C) ebb currents.
D) gravity and inertia.

Question 33

Which of the following bodies is the largest?

A) Earth.
B) Sun.
C) Moon.
D) Mars

Question 34

Tractive forces include gravitational forces from both the moon and the sun.

Question 35

For tides as long waves, the amphidromic point corresponds to the wave crest.

Question 36

Tidal bulges are formed as the moon's gravity pulls the surface of the ocean towards the moon.

Question 37

The type of tide associated with the full and new moons are:

A) neap tides.
B) spring tides.
C) diurnal tides.
D) tidal currents.

Question 38

What body generates the strongest tractive forces?

A) The moon
B) The sun
C) The Earth
D) the moon and the sun

Question 39

There can only be one high tide and one low tide per tidal day for any given area.

Question 40

Tidal friction is gradually slowing Earth's rotation.

Question 41

What are the amphidromic points of the world ocean and how are they determined?

Question 42

Tides are shallow-water waves. Explain this statement.

Question 43

Explain the relative influence of the sun and the moon on tides.

Question 44

Can tides be predicted? Explain why or why not and give examples of factors that may render tidal predictions inaccurate.

Question 45

How can tidal energy be used by humans?