Oceanography Chapter 9

The ________ of the Moon determines the position of the tidal bulges on Earth.

declination

Grunion spawning patterns have evolved to take advantage of ________ associated with tides.

deposition and erosion

What are Earth's three different tidal patterns called?

diurnal, semidiurnal, and mixed

When is the current moving into or out of the bay moving at its fastest velocity?

during the ebb current between higher high water and lower low water

A boat is most likely to be carried out to sea from a harbor by a(n) __________.

ebb current

Water flowing out of an enclosed basin due to the tides is called a/an:

ebb current.

On the side of Earth closest to the Moon, gravitational forces __________ the centripetal forces.

exceed

How many semidiurnal tides would you expect during one tidal period?

four tides

What pattern of tides would you expect to see for a mixed tidal system?

four tides of different heights

The attraction between Earth and the Moon is an example of ________ force.

gravitational

The Moon's influence on Earth's tides is __________ the influence of the Sun.

greater than

A spring tide:

has very high high tides and very low low tides

In the SmartFigure, what does HSW stand for?

high slack water

If the side of the Earth that faces the moon experiences a high tide, then the side of the Earth that is opposite from the moon will have a/an:

high tide

Disadvantages of tidal power plants relative to conventional thermal plants include higher initial plant costs, periodicity of tidal currents, and __________.

impacts on the marine environment

The tide-generating force varies:

inversely with the cube of the distance between the objects.

In order to keep up with the tidal force of the Moon, the tidal bulge waveform moves across Earth's oceans at a speed of about 1,600 ________ per hour.

kilometers

Compared with a solar day, a lunar day is:

longer than a solar day.

What type of tidal pattern is illustrated in the SmartFigure?

mixed

The most common tidal pattern around the world are:

mixed tides.

The weakest gravitational force caused by the Moon is called the __________, which is found at the point on Earth farthest from the Moon.

nadir

The minimum tidal range happens during ________ tides.

neap

There is destructive interference between the lunar and solar tidal bulges during ________ tides.

neap

An area that experiences diurnal tides will have:

one high tide and one low tide daily

Whirlpools can be created in some restricted shallow passages due to ________.

reversing tidal currents

The graph shown is an example of a ________ tidal pattern.

semidiurnal

You have just arrived for a vacation on the Oregon coast, and you wish to explore some tide pools while you are there. You hear the local weatherman say that there will be a minus tide at 7 a.m. tomorrow. You should __________.

set your alarm to wake you early; this may be your best chance for tidepooling

The maximum tidal range happens during ________ tides.

spring

There is constructive interference between the lunar and solar tidal bulges during ________ tides.

spring

Some of the tide height numbers in your tide table are preceded by minus signs (or in some cases printed in red). This tells you that __________.

spring tides are occurring

When would the oceans experience the greatest tidal range?

when Earth is in perihelion and the Moon is in perigee

Neap tides occur:

when the moon is in quadrature.

During what time period(s) is the tide going out in the figure? Choose all that apply.

- 0 to 6 lunar hours - 12 to 18 lunar hours

Which of the following existing or proposed tidal power plants would, upon completion, produce the most electricity?

Severn Estuary

What is the difference between perihelion and aphelion?

Perihelion is when Earth is closest to the Sun, and aphelion is when it is farthest from the Sun.

Based on the map of worldwide tidal patterns, New Zealand experiences which of the following?

Semidiurnal Tidal Pattern

If you are standing at 28 degrees north latitude, you will experience a high tide when the Moon is directly overhead. When will low tide occur?

Six lunar hours later

Why does the Moon reach perigee two days before it completes its 29-and-a-half-day lunar cycle?

The Moon's orbit around Earth shifts position over time.

In the United States semidiurnal tides commonly occur along the:

Atlantic coast.

The center of mass of the Earth-Moon system is called the:

barycenter

A tidal current can produce a rapidly spinning body of water called a vortex or:

whirlpool.

The ________ force pulls an orbiting body toward the center of that orbit.

centripetal

Spring tide occurs about:

twice per month.

Resultant forces result in __________ tidal bulge(s) on Earth.

two

In the SmartFigure's typical tidal curve for a bay, how many high and low tides are in one lunar day?

two high tides and two low tides

An area that experiences semidiurnal tides will have:

two high tides and two low tides of nearly equal height daily.

How many spring and neap tides occur each month?

two spring tides and two neap tides

How many diurnal tides would you expect during one tidal period?

two tides

The Bay of Fundy is well known for which tidal characteristic?

very high tidal range

A neap tide has:

very low tidal range.

Which of the following statements about tides in a simple tidal bulge model is/are true? Choose all that apply.

- A lunar or solar eclipse can occur only when the Moon is in syzygy. - Spring tides result from constructive interference between the solar and lunar tidal bulges. - Neap tides result from destructive interference between the solar and lunar tidal bulges. - Tides are greatest when the Moon is at perigee and Earth is at perihelion.

Which of the following statements is/are true regarding neap tides? Choose all that apply.

- Neap tides occur when there is a small tidal range. - High tides are low. - Neap tides occur during first quarter moon and third quarter moon.

Which of the following statements is/are true concerning spring tides? Choose all that apply.

- Spring tides have high high tides. - Spring tides occur when the Earth, Moon, and Sun are aligned.

Of the following statements about the force of gravity between two bodies, which is/are true? Choose all that apply.

- The force of gravity between two bodies increases with an increase in mass. - The force of gravity between two bodies is most affected by a change in distance. - The force of gravity between two bodies decreases as distance increases.

Of the following statements about the monthly tidal cycle, which is/are true? Choose all that apply.

- The full moon and the new moon affect the tides about the same. - Spring tides occur twice a month. - The full moon is associated with spring tide conditions. - Neap tides occur twice a month.

Of the following statements about the contribution of the Sun and the Moon to Earth's tides, which is/are true? Choose all that apply.

- The lunar tidal bulges are about twice the size of the solar tidal bulges. - The Sun's contribution to the tides is less than that of the Moon. - The Moon exerts over twice the gravitational pull of the Sun on Earth's tides because of its proximity to Earth.

Which of the following statements about tidal patterns and tidal charts is/are true? Choose all that apply.

- The tidal range is the difference in height between a high tide and a low tide. - A tidal day is 24 hours and 50 minutes long. - A semidiurnal tidal pattern has two low tides every tidal day. - A mixed tidal pattern has two lows of unequal height and two highs of unequal height every tidal day.

Of the following statements about the tides, which is/are true? Choose all that apply.

- The tides are caused by an imbalance between the centripetal force and the gravitational force of the Moon and the Sun. - Both Earth and the Moon orbit around their common center of mass, called the barycenter. - There are two tidal bulges on Earth caused by the Moon: one facing the Moon, and the other facing away from the Moon. - Although we observe the tides coming in and going out, in reality, Earth is rotating into and out of various tidal bulges, which produces changing tides.

Which of the following statements is/are true regarding Earth and the Moon? Choose all that apply.

- There are two lunar tidal bulges and two solar tidal bulges. - Earth rotates counterclockwise on its axis, or from west to east.

Where is/are Earth's tidal bulge(s) located?

- at the zenith - at the nadir

Which phase(s) of the moon result in a low tidal range? Choose all that apply.

- first quarter moon - third quarter moon

Maximum tides occur once every ________ years when Earth is closest to the Sun, the Moon is closest to the Earth and the Earth-Moon-Sun system is aligned.

1600

A lunar day is:

24 hours and 50 minutes in duration

It is Wednesday, and you are planning a fishing trip for this coming Saturday. You have heard that fishing is best at your chosen spot when the ebb current begins to flow, so you wish to start fishing at high tide. You do not have a tide table, but you have noted that today's high tide was at 1:10 p.m. At what time on Saturday should you plan to arrive and start fishing?

3:40 p.m.

In the figure above, assume black arrow (1) is the gravitational force and black arrow (2) is the centripetal force on the surface of a hypothetical planet. Which of the red arrows would represent the resultant force?

B

Based on the map of worldwide tidal patterns, Texas experiences which of the following?

Diurnal Tidal Pattern

The graph shown is an example of which of the following tidal patterns?

Diurnal Tidal Pattern

Which of the following statements concerning tides is correct?

Diurnal tides are a tidal pattern in which there is one high tide and one low tide in a lunar day.

What is Newton's Law of Universal Gravitation?

F = Gm1m2/r2

Which of the following coasts is an example of a diurnal tidal pattern?

Gulf of Mexico

Based on the map of worldwide tidal patterns, California experiences which of the following?

Mixed Tidal Pattern

Where on Earth is the centripetal force toward the Moon the greatest?

The centripetal force is the same everywhere on Earth.

In a bay experiencing a mixed tidal pattern, which of the following represents the highest ebb or flood velocity?

The ebb current between the higher high water tide and the lower low water tide

Which of the following statements comparing a tidal power electricity-generating with a conventional thermal power plant is correct?

The initial cost of building a tidal power electricity-generating plant may are higher.

How is a semidiurnal period related to a tidal day?

The semidiurnal period is half as long as a tidal day.

The Full Moon is immediately followed by the ________ phase of the Lunar Cycle.

Waning gibbous

Which of the following coasts has both semidiurnal and mixed tidal patterns?

West Coast of South America

Which of the following coasts is an example of a mixed tidal pattern?

West Coast of The United States

The maximum tidal currents are reported:

about half way between high and low tides.

The center of an open ocean tidal system is called a/an:

amphidromic point.

A relatively small tidal range could be expected __________.

at an amphidromic point

Where on Earth is the gravitational attraction toward the Moon the greatest?

at the zenith

In the United States mixed tides commonly occur along:

the Pacific coast.

What is the coastal tidal range?

the difference in sea level between a successive high and low tide

What causes variation in Earth's tides over time?

the elliptical orbits of the Moon around Earth, and Earth around the Sun.

Tidal forces result in two tidal bulges because __________.

the supplied gravitational forces at various points within the planet differ from the centripetal force

The tides are considered an example of shallow-water waves because the tidal bulges have a wavelength that is on the order of __________.

thousands of kilometers

This wave formed on a river by a flood current is called a/an:

tidal bore.

The low and high tides experienced on Earth are the result of __________.

tidal bulges

What do we call the time that passes between two high tides?

tidal period

The vertical difference between consecutive high and low tides is called the:

tidal range.

The force that creates two simultaneous ocean bulges on opposite sides of Earth, directed toward or away from the Moon, is called the ________ force.

tide-generating