Ocean waves Currents Tides & Tsunamis MCQ Quiz - Objective Question with Answer for Ocean waves Currents Tides & Tsunamis - Download Free PDF

The correct answer is Warm Current.

Key Points

• Warm oceanic current is generally formed in the equatorial and tropical regions.
• Warm currents generally flow from lower latitudes towards higher latitudes.
• While Cold currents flow from higher latitudes towards lower latitudes.
• In the region where warm oceanic currents flow, humid climatic conditions are formed and in the regions where cold oceanic currents flow, arid climatic conditions are formed.
• Due to cold oceanic currents deserts are formed.
• In the regions where warm and cold oceanic currents meet, nutrients are found which increase the growth rate of phytoplankton.

Additional Information

Nature of Some important Oceanic currents:

The correct answer is seven.

Key Points

• There is a seven-day interval between the spring tides and neap tides.
• Tides are the rise and fall of sea levels caused by the combined effects of the gravitational forces exerted by the Moon and the Sun, and the rotation of the Earth.
• There are two types of tides namely, spring tides and neap tides depending upon the relative positions of the sun, the earth, and the moon.
• Spring tides:
  • When the sun, the moon, and the earth are in a straight line, the height of the tide will be higher.
  • These are called spring tides and they occur twice a month, one during the full moon period and another during the new moon period.
• Neap tides:
  • Normally, there is a seven-day interval between the spring tides and neap tides.
  • At this time the sun and moon are at right angles to each other and the forces of the sun and moon tend to counteract one another.
  • The Moon's attraction, though more than twice as strong as the sun's, is diminished by the counteracting force of the sun's gravitational pull.
  • Like spring tides, these tides also occur twice a month.

The correct answer is 1 only.

Key Points

• L-Waves (Long Waves) travel along the Earth's surface, following its circumference.
• They are also known as surface waves and are generated during earthquakes.
• L-Waves are slower compared to P-Waves (Primary Waves) and S-Waves (Secondary Waves).
• The speed of L-Waves is not constant and depends on the Earth's material properties and the nature of the medium.
• They cause significant destruction due to their high amplitude and horizontal motion.

Additional Information

• P-Waves: Primary waves are the fastest seismic waves, traveling through solids, liquids, and gases.
• S-Waves: Secondary waves are slower than P-Waves and can only travel through solids.
• Seismic Wave Categories: Seismic waves generated during earthquakes are categorized as body waves (P and S waves) and surface waves (L and Rayleigh waves).
• Rayleigh Waves: Another type of surface wave that travels in an elliptical motion and causes vertical displacement.
• Earthquake Impact: Surface waves, including L-Waves, are primarily responsible for the damage to buildings and infrastructure during an earthquake.

The correct answer is 3 only.

Key Points

• West Wind Drift is a cold ocean current that flows in the Southern Hemisphere and is also known as the Antarctic Circumpolar Current.
• The current is driven by the strong westerly winds, moving from west to east around Antarctica.
• It plays a crucial role in regulating the global climate by facilitating the exchange of heat and nutrients between the world's oceans.
• Alaska Current and North Atlantic Drift are warm currents, not cold currents, and flow in the Northern Hemisphere.

Additional Information

• Ocean Currents:
  • Ocean currents are continuous, directed movements of seawater generated by forces such as wind, the Coriolis effect, and temperature/salinity differences.
  • They are categorized into warm and cold currents depending on their temperature relative to the surrounding water.
• Warm Currents: These currents, such as the North Atlantic Drift and Alaska Current, originate near the equator and transport warm water to higher latitudes.
• Cold Currents: These currents, like the West Wind Drift and Labrador Current, transport cold water from polar areas to lower latitudes.
• Antarctic Circumpolar Current: This is the largest ocean current in the world, connecting the Atlantic, Pacific, and Indian Oceans and playing a key role in the global conveyor belt of ocean circulation.
• Impact of Ocean Currents: They influence global climate patterns, marine biodiversity, and even human activities such as fishing and shipping.

The correct answer is Energy and electricity.

Key Points

• Tidal and wave energy are forms of renewable energy harnessed from the motion and gravitational effects of the ocean.
• Tidal power is generated by capturing the kinetic and potential energy from the rise and fall of tides, while wave power utilizes the energy from surface waves.
• This energy can be converted into electricity using technologies like tidal barrages, underwater turbines, and wave energy converters.
• Wave and tidal energy are predictable and reliable compared to solar and wind energy, making them a promising source of clean power.
• Countries like the UK, France, and South Korea have developed significant tidal power plants, while wave energy projects are being tested globally.

Additional Information

• Tidal Barrage: A dam-like structure that captures the potential energy of tides by trapping water in a reservoir during high tides and releasing it through turbines during low tides.
• Wave Energy Converters: Devices designed to capture and convert the mechanical energy of ocean waves into electrical energy.
• Environmental Impact: While tidal and wave energy are clean sources, they can impact marine ecosystems, including altering habitats and affecting aquatic species.
• Global Potential: The global potential for tidal and wave energy is estimated to be around 1,200 TWh/year, enough to power millions of households.
• Challenges: High initial costs, maintenance in harsh marine environments, and limited suitable locations are some of the key challenges in harnessing ocean energy.

The Correct Answer is Kuroshio Current.

Important Points

• Kuroshio Current:
  • It is also known as Japan Current and flows from Taiwan to the Bering Strait.
  • It is a warm current of the Pacific Ocean.
• Humboldt Current:
  • It is a Cold current of the Pacific Ocean.
  • Flows northwards along the western coast of South America and is actually the continuation of west wind drift.
• Labrador Current:
  • It is a Cold current of the Atlantic Ocean.
  • It Originates in the Baffin Bay drifts south eastwards Baffin and Greenland and merges with the Gulf Stream of New Foundland.
• Canaries Current:
  • It is a cold current of the Atlantic Ocean.
  • It is the continuation of North Atlantic Drift along the western coast of the Iberian Peninsula and North Africa in the southern direction .

The correct answer is Tide.

Key Points

• The rhythmic rise and fall of the ocean twice a day is called a tide.
• The intense gravitational force exerted by the sun and the moon on the surface of the earth induce tides.

Additional Information

• When water covers most of the shore by rising to its maximum level, it is known as high tide.
• It is low tide as the waterfalls to its lowest level and recedes from the sea.
• The water of Earth closer to the moon is drawn under the influence of the gravitational force of the moon which creates a high tide.
• The sun, the moon, and the earth are in the same line during the full moon and new moon days and the tides are highest. These tides are called the spring tides.
• But when the moon is in its first and last quarter, the ocean waters are drawn in diagonally opposite directions through the gravitational force of the sun and earth resulting in low tides. These tides are called neap tides.
• High tides help in navigation as they raise the level of water closer to the coast. This makes it easier for ships to enter the harbour.
• High tides assist with fishing as well as much more fish, move closer to the sea during the high tide. This helps fishermen to have an abundant harvest.
• The rise and fall of water due to tides is being used in some places to generate electricity.

Earth's Tides

The correct answer is Option 4 i.e. Falkland Current.

The Atlantic Ocean is divided into two parts, by the Equatorial Counter Current, with the North(ern) Atlantic Ocean and the South(ern) the Atlantic Ocean at about 8°N

Ocean currents in the Atlantic Ocean include the below-given currents:

• Gulf stream:
• Another part of the Cayenne current heads northwards east of the Antilles as the Gulf Stream.
• The Gulf stream is one of the strongest ocean currents.

Hence, option 4 is the correct answer.

Mistake Points

Labrador Current:

The correct answer is Agulhas current.

• The Agulhas Current is the western boundary current of the South Indian Ocean.
• It flows down the east coast of Africa from 27°S to 40°S.

Important Points

• Currents in the Indian Ocean include the following:
  • The North-East Monsoon Drift
  • The South West Monsoon Drift
  • North Equatorial Current (Warm)
  • South Equatorial Current (Warm)
  • Somali Current (Cold)
  • Mozambique Current (Warm)
  • Madagascar Current (Warm)
  • Agulhas Current (Warm)
  • West Australian Current (Cold)

Additional Information

• The Florida Current is a thermal ocean current that flows from the Straits of Florida around the Florida Peninsula and along the southeastern coast of the United States.
• Canary Current, part of a clockwise-setting ocean-current system in the North Atlantic Ocean.
• Oyashio Current or the Kurile current is the western boundary current in the subpolar gyre of the North Pacific.
• It originates in the Bering Sea and flows south-west off the Kuril Islands to meet the Kuroshio Current east of northern Japan.

Tsunami is a Japanese word with the English translation, "harbour wave."

Key Points:

Represented by two characters, the top character, "tsu," means harbor, while the bottom character, "nami," means "wave."

In the past, tsunamis were sometimes referred to as "tidal waves" by the general public, and as "seismic sea waves" by the scientific community.

The term "tidal wave" is a misnomer; although a tsunami's impact upon a coastline is dependent upon the tidal level at the time a tsunami strikes, tsunamis are unrelated to the tides.

Tides result from the imbalanced, extraterrestrial, gravitational influences of the moon, sun, and planets. The term "seismic sea wave" is also misleading. "Seismic" implies an earthquake-related generation mechanism, but a tsunami can also be caused by a nonseismic event, such as a landslide or meteorite impact.

Causes a Tsunami

• Subduction Zones are Potential Tsunami Locations
• Most tsunamis are caused by earthquakes generated in a subduction zone, an area where an oceanic plate is being forced down into the mantle by plate tectonic forces. The friction between the subducting plate and the overriding plate is enormous. This friction prevents a slow and steady rate of subduction and instead the two plates become "stuck."
• Accumulated Seismic Energy
• As the stuck plate continues to descend into the mantle, the motion causes a slow distortion of the overriding plate. The result is an accumulation of energy very similar to the energy stored in a compressed spring. Energy can accumulate in the overriding plate over a long period of time - decades or even centuries.
• Earthquake Causes Tsunami
• Energy accumulates in the overriding plate until it exceeds the frictional forces between the two stuck plates. When this happens, the overriding plate snaps back into an unrestrained position. This sudden motion is the cause of the tsunami - because it gives an enormous shove to the overlying water. At the same time, inland areas of the overriding plate are suddenly lowered.

The correct answer is seven.

Key Points

• There is a seven-day interval between the spring tides and neap tides.
• Tides are the rise and fall of sea levels caused by the combined effects of the gravitational forces exerted by the Moon and the Sun, and the rotation of the Earth.
• There are two types of tides namely, spring tides and neap tides depending upon the relative positions of the sun, the earth, and the moon.
• Spring tides:
  • When the sun, the moon, and the earth are in a straight line, the height of the tide will be higher.
  • These are called spring tides and they occur twice a month, one during the full moon period and another during the new moon period.
• Neap tides:
  • Normally, there is a seven-day interval between the spring tides and neap tides.
  • At this time the sun and moon are at right angles to each other and the forces of the sun and moon tend to counteract one another.
  • The Moon's attraction, though more than twice as strong as the sun's, is diminished by the counteracting force of the sun's gravitational pull.
  • Like spring tides, these tides also occur twice a month.

The correct answer is Kuroshio current.

Key Points

• Kuroshio current is a warm current.
• A north-flowing ocean current on the west side of the North Pacific Ocean is the Kuroshio current, also known as the Japan current. It transports the warm water north to the area of Polar.
• The warm waters of the Kuroshio Current sustain the coral reefs of Japan, the northernmost coral reefs in the world. 
• It is the western boundary current of the subtropical North Pacific gyre.
• It originates from the Pacific North Equatorial Current, which divides into two on the east coast of Luzon, Philippines, to form the southward-flowing Mindanao Current and the more important northward-flowing Kuroshio Current.

Important Points

• The Canary Current is a surface current powered by wind that is part of the Gyre of the North Atlantic. This eastern boundary current branches south from the North Atlantic Current and flows southwest about as far as Senegal where it turns west and later joins the Atlantic North Equatorial Current. The current is named after the Canary Islands. 
• Labrador Current is a cold current that runs south from the Arctic Ocean around the Labrador coast and travels through Newfoundland, heading south down the eastern coast of Canada near Nova Scotia.
• The Oyashio current in the western North Pacific Ocean is a cold subarctic ocean current that runs south and circulates counterclockwise. 

The correct answer is Peru.

Key Points

• El Nino is a surroundings layout that depicts the odd warming of surface waters in the Japanese tropical Pacific Ocean.
• El Nino is a weather circumstance that happens in the Pacific Ocean.
• The term El Niño (Spanish for 'the Christ Child') refers to a warming of the ocean surface, or above-average sea surface temperatures, in the central and eastern tropical Pacific Ocean.
• The low-level surface winds, which normally blow from east to west along the equator (“easterly winds”), instead weaken or, in some cases, start blowing the other direction (from west to east or “westerly winds”).
• El Niño recurs irregularly, from two years to a decade, and no two events are exactly alike. El Niño events can disrupt normal weather patterns in the United States and globally.
• Los Angeles Nina is a surroundings layout that depicts the cooling of floor sea waters along the tropical west shore of South the united states.
• The Mediterranean Sea envelops endless islands, a number of them being volcanic starting. The two by using a huge margin biggest islands are Sicily and Sardinia.

Additional Information

The correct answer is Two.

Key Points

• The gravitational attraction between the Earth, the Moon, and the Sun causes tides in the Earth's oceans.
• There are typically two high tides and two low tides in most locations around the world in a 24-hour period, resulting in a semi-diurnal tide pattern.
• Each high tide is followed by a low tide, and then there's another high tide and low tide.
• The time between successive high tides (or low tides) is approximately 12 hours and 25 minutes, which means there are about two high tides and two low tides in a day.
• This is because the Moon's gravitational pull causes a bulge of water on the side of the Earth facing the Moon (the high tide), and another bulge on the opposite side of the Earth (the low tide).
• The Sun's gravitational pull also contributes to the tides, though its effect is about half that of the Moon's due to the Sun's greater distance.

The correct answer is the Gulf Stream.

• Gulf Stream does not flow into the Pacific Ocean. It is a warm Atlantic Ocean Current which originates from the Gulf of Mexico.
• An ocean current is a continuous, directed movement of seawater generated by a number of forces acting upon the water, including wind, the Coriolis effect, waves, and temperature and salinity differences.

List of Ocean Currents of the World