The tides whose height is 20 percent more than normal tide are called
- A.spring tides
- B.neap tides
- C.apogean and perigean tides
- D.daily and semi-diurnal tides
Correct answer
Explanation
The correct answer is A, spring tides. Spring tides rise about 20 percent higher than normal tides because the Sun and the Moon pull along the same line.
Spring tides occur twice a month, at new moon and full moon, when the Sun, the Moon and the Earth are in a straight line. Their combined pull gives higher high tides and lower low tides. Neap tides come about seven days later, at the first and last quarters, when the Sun and the Moon are at right angles to each other as seen from the Earth; their pulls partly cancel, and the tidal range is smallest.
B is wrong: neap tides are lower than normal tides.
C is wrong: apogean and perigean tides depend on the Moon's distance from the Earth, not on the Sun and Moon lining up.
D is wrong: daily and semi-diurnal tides are classed by how often they occur, not by their height.
Exam tip: spring tide = new or full moon, highest range; neap tide = quarter moons, lowest range.
Practice Questions
View allConsider the following places of India :
1. Itanagar
2. Imphal
3. Agartala
4. Aizawl
Which one of the following is the correct chronological order of the above places in terms of sunrise time?
- A.3-2-1-4
- B.2-1-4-3
- C.1-4-3-2
- D.4-3-2-1
Show answer
The sun rises first in the place farthest east, so the order follows longitude: Imphal, Itanagar, Aizawl and then Agartala.
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- A.Adelaide
- B.Darwin
- C.Hobart
- D.Brisbane
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Viticulture, the growing of grapes, is a hallmark of Adelaide, which is surrounded by Australia's best-known wine regions. Adelaide, the capital of South Australia, has a Mediterranean climate with hot, dry summers and mild, wet winters, the conditions grapevines like best.
Read the full explanation →Which of the following statements regarding Barchan is/are correct ?
1. It is a crescent shaped mound of sand, which is deposited by the wind blowing constantly from one direction in a desert.
2. The windward side has a convex steep slope with maximum height at the centre.
3. Two ends of Barchan are called horns and point opposite to the direction the wind blows.
Select the answer using the code given below :
- A.1 only
- B.1 and 2 only
- C.2 and 3 only
- D.1, 2 and 3
Show answer
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Read the full explanation →Which part of India has the Kalakot tertiary coal field ?
- A.Brahmaputra river basin of Assam
- B.Damodar river basin of Jharkhand and West Bengal
- C.Himalayan mountain region
- D.Cardamom hills in Kerala
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Read the full explanation →National Water Academy, a centre of excellence in training and capacity building in water resource, is located at
- A.New Delhi
- B.Kolkata
- C.Pune
- D.Chennai
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The National Water Academy functions at Khadakwasla in Pune, Maharashtra, under the Central Water Commission. The academy began in 1988 as the Central Training Unit of the Central Water Commission and was renamed the National Water Academy in 1997.
Read the full explanation →