651: Which of the following statements about the monsoon in India is incorrect?
(a) South-West monsoon are on-shore winds
(b) North-East monsoon are off-shore winds
(c) The monsoons retreat gradually
(d) The onset of the monsoon is from West Bengal only
652: Through which one of the following Straits, does a tunnel connect the United Kingdom and France ?
(a) Strait of Gibraltar
(b) Denmark Strait
(c) Strait of Dover
(d) Davis Strait
Explanation:
Dover Strait is between English Channel and North Sea. Dover is the strait at the narrowest part of the English Channel. The shortest distance across the strait is from the South Foreland, some 6 km north-east of Dover in the country of kent, England. The strait lies at the east end of the English Channel, where it joins the North Sea. Its width is the shortest distance between France and England.
653: Consider the following pairs :
Tribe : State
1. Limboo (Limbu) : Sikkim
2. Karbi : Himachal
3. Dongaria Kondh : Odisha
4. Bonda : Tamil Nadu
Which of the above pairs are correctly matched?
(a) 1 and 3 only
(b) 2 and 4 only
(c) 1, 3 and 4 only
(d) 1, 2, 3 and 4
Explanation:
Tribe : State
1. Limboo (Limbu) : Sikkim
2. Karbi : Assam
3. Dongaria Kondh : Odisha
4. Bonda : Orissa
654: Swamps are seen in the Siberian rivers because
(a) Freezing of the river near the mouth prevents water to flow to the sea
(b) Rivers are too narrow
(c) Rivers are heavily drained by the large network of canals
(d) Railway bridges built across the rivers obstruct the flow
655: The formation of ozone hole in the Antarctic region has been a cause of concern. What could be the reason for the formation of this hole?
(a) Increased temperature at polar region due to global warming
(b) Presence of prominent polar front and stratospheric Clouds and inflow of chlorofluorocarbons
(c) Absence of polar front and stratospheric clouds and inflow of methane and chlorofluorocarbons
(d) Presence of prominent tropospheric turbulence and inflow of chlorofluorocarbons
Explanation:
The severe depletion of stratospheric ozone in Antarctic winter is known as the "ozone hole". The formation of the Antarctic ozone hole is due to abundant reactive halogen gases, temperatures low enough to form polar stratospheric clouds (PSCs), isolation of air from other stratospheric regions, and sunlight. Presence of prominent polar front and stratospheric clouds; and inflow of chlorofluorocarbons accelerates the ozone layer formation in Antarctica.
Hence option B is the correct one.