GS Geography Quiz for IAS Prelims – Movements of Ocean Water II

Geography is so vast in its syllabus that it covers the most part of the General Studies for the IAS Prelims Exam. A widespread understanding of the geography subject is needed to answer all the questions of the IAS Prelims Exam.

UPSC IAS Prelims Exam 2017 : GS Geography Study Material

The IAS aspirants cannot overlook the geography portion because there are various aspects of geography which enormously helps in the overall General Studies Preparations. So, it’s advisable to prepare geography from standard sources starting with NCERTS.

1. Which place in India has the potential for generation of tidal energy:

1) Gulf of Cambay
2) Gulf of Kutch
3) Gulf of Mannar

Choose the correct code:

a. 1 and 2
b. 2 and 3
c. 1 and 3
d. 1, 2 and 3

Answer: a

Explanation:

Tidal Energy is one of the new and emerging technologies, which s commercially not viable and still in research and development (R&D) stage. India has a long coastline with the estuaries and gulfs where tides are strong enough to move turbines for electrical power generation.

The Gulf of Cambay and tie Gulf of Kutch in Gujarat on the west coast have the maximum tidal range of 11 m and 8 m with an average tidal range of 8.77m and 5.Z5m respectively. The Ganges Delta in the Sundarbans is approximately 5m with an average tidal range of 2.97m.

Table: Tidal Energy Potential in India

No tidal power generation plant has been installed in India due to its high cost of generation of electricity and lack of techno-economic viability.

2. Which of the following statement is true regarding the ebb and flow of tides?

a. The time between the high tide and low tide, when the water level is falling, is called the flow.
b. The time between the low tide and high tide, when the tide is rising, is called the ebb.
c. Both (a) and (b)
d. None of the above

Answer: d

Explanation:

Ebb and flow are two phases of the tide or any similar movement of water. The ebb is the outgoing phase when the tide drains away from the shore, and the flow is the incoming phase when the water rises again. They are also called as ebb and flood and flood drain of the tide or similar movement of the water.

Tidal currents occur in conjunction with the rise and fall of the tide. The vertical motion of the tides near the shore causes the water to move horizontally, creating currents. When a tidal current moves toward the land and away from the sea, it floods. When it moves toward the sea away from the land, it ebbs. These tidal currents that ebb and flood in opposite directions are called rectilinear or reversing currents.

UPSC IAS Prelims Exam 2017 : the oceans

3. Consider the followings statements regarding the spring tides:

1) During spring tide, the sun, the moon and the earth are in a straight line.

2) The height of the tide will be higher during spring tide.

3) Spring tides occur once a month.

Which of the above statements is true?

a. 1 and 2
b. 2 and 3
c. 1 and 3
d. 1, 2 and 3

Answer: b

Explanation:

The height of rising water (high tide) varies appreciably depending upon the position of sun and moon with respect to the earth. Spring tides and neap tides come under this category.

The position of both the sun and the moon in relation to the earth has direct bearing on tide height. 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 on full moon period and another during new moon period.

4. Which of the following names of the positions moon, sun and earth are correctly matched?

1) Perihelion- When the earth is closest to the sun

2) Perigee- when the moon’s orbit is closest to the earth

3) Apogee- When the earth is farthest from the sun

Which of the above statements is true?

a. 1 and 2
b. 2 and 3
c. 1 and 3
d. 1, 2 and 3

Answer: b

Explanation:

Apogee and perigee refer to the distance from the Earth to the moon. Apogee is the farthest point from the earth. Perigee is the closest point to the earth and it is in this stage that the moon appears larger. Looking at the moon in the sky without anything to compare it to, you wouldn't notice any size difference. But the difference in size can in fact be quite significant.

The perihelion is the point in the orbit of a celestial body where it is nearest to its orbital focus, generally a star. It is the opposite of aphelion, which is the point in the orbit where the celestial body is farthest from its focus.

IAS Prelims Questions on Oceanography

5. Consider the followings statements regarding the Neap tides and spring tides:

1) There is a seven day interval between the spring tides and neap tides.

2) During neap tide, the sun and moon are at right angles to each other.

Which of the above statements is true?

a. Only 1
b. Only 2
c. Both 1 and 2
d. Neither 1 nor 2

Answer: b

Explanation:

Normally, there is a seven day interval between the spring tides and neap tides. During neap tide, 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.

6. The height of rising water varies depending upon the position of sun and moon with respect to the earth. Which of the following statements is true in this regard:

a. When the moon’s orbit is closest to the earth, unusually high and low tides occur.
b. During perigee, the tidal range is much less than normal.
c. When the earth is farthest to the sun, tidal ranges are also much greater.
d. All of the above

Answer: a

Explanation:

Once in a month, when the moon’s orbit is closest to the earth (perigee), unusually high and low tides occur. During this time the tidal range is greater than normal. Two weeks later, when the moon is farthest from earth (apogee), the moon’s gravitational force is limited and the tidal ranges are less than their average heights.

When the earth is closest to the sun (perihelion), around 3rd January each year, tidal ranges is also much greater, with unusually high and unusually low tides. When the earth is farthest from the sun (aphelion), around 4th July each year, tidal ranges are much less than average.

Current Affairs Quizzes 2016

7. Consider the following statements regarding Tidal Energy generation:

1) The difference in water height from low tide and high tide is potential energy.

2) Tidal water is captured in a barrage across an estuary during Low tide and forced through a hydro-turbine during high tide.

3) To capture sufficient power from the tidal energy potential, the height of high tide must be at least five meters (16 feet) greater than low tide.

Which of the above statements is true?

a. 1 and 2
b. 2 and 3
c. 1 and 3
d. 1, 2 and 3

Answer: c

Explanation:

The tidal cycle occurs every 12 hours due to the gravitational force of the moon. The difference in water height from low tide and high tide is potential energy. Similar to traditional hydropower generated from dams, tidal water can be captured in a barrage across an estuary during high tide and forced through a hydro-turbine during low tide. To capture sufficient power from the tidal energy potential, the height of high tide must be at least five meters (16 feet) greater than low tide.

There are only approximately 20 locations on earth with tides this high and India is one of them. The Gulf of Cambay and the Gulf of Kutch in Gujarat on the west coast have the maximum tidal range of 11m and 8m with an average tidal range of 6.77m and 5.23m respectively.

UPSC IAS Study Material for Civil Services Prelims 2017