481: The Narmada river flows to the west, while most other large peninsular rivers flow to the east Why?
1. It occupies a linear rift valley.
2. It flows between the Vindhyas and the Satpuras.
3. The land slopes to the west from central India.
Select the correct answer using the codes given below.
(a) 1 only
(b) 1 and 3
(c) 2 and 3
(d) None
Explanation:
Here statement 1 and 2 both are correct about Narmada river, but statement 1 is the actual reason about the Narmada river flowing to the west.
482: Why does the Government of India promote the use of 'Neem-coated Urea' in agriculture?
(a) Release of Neem oil in the soil increases nitrogen fixation by the soil microorganisms
(b) Neem coating slows down the rate of dissolution of urea in the soil
(c) Nitrous oxide, which is a greenhouse gas, is not at all released into atmosphere by crop fields
(d) It is a combination of a weedicide and a fertilizer for particular crops
483: Normally, the temperature decreases with the increase in height from the Earth's surface, because
1. the atmosphere can be heated upwards only from the Earth's surface
2. there is more moisture in the upper atmosphere
3. the air is less dense in the upper atmosphere
Select the correct answer using the codes given below :
(a) 1 only
(b) 2 and 3 only
(c) 1 and 3 only
(d) 1, 2 and 3
Explanation:
Since the atmosphere is warmed from the ground up, and since the air is at its most dense near the surface of the earth, the air near the surface is going to be able to retain much more heat than the air at higher elevations due to the increased amounts of air molecules; higher elevations have fewer air molecules and consequently can't retain as much heat. So, even though you would be much closer to the sun if you were standing on top of a mountain, the air temperature would be considerably less than it would be at sea level.
So answer is (C).
484: In India, the ports are categorized as major and non-major ports. Which one of the following is a non-major port?
(a) Kochi (Cochin)
(b) Dahej
(c) New Mangalore
(d) Paradip
Explanation:
(a) on the West Coast: Mumbai Jawaharlal Nehru Port at Jhava Sheva, Kandla, Mormugao New Mangalore and Cochin.
(b) on the East Coast: Kolkata/Haldia, Paradip, Chennai, Visakhapatanam, Ennore and Tuticorin.
485: On 21st June, the Sun
(a) does not set below the horizon at the Arctic Circle
(b) does not set below the horizon at Antarctic Circle
(c) shines vertically overhead at noon on the Equator
(d) shines vertically overhead at the Tropic of Capricorn
Explanation:
21st June is the longest day of the year as countries lying to the north of the equator, including India, witness Summer Solstice.The summer solstice occurs exactly when the earths axial tilt is most inclined towards the sun at its maximum of 23 degrees 26.During summer solstice, the Northern Hemisphere witnesses its longest day of the year while the Southern Hemisphere sees its shortest day.
On the June solstice, the Earths North Pole is at its maximum tilt toward the sun. At this time, the sun appears directly overhead at 23.5 degrees north latitude, along the Tropic of Cancer.
Around the Arctic Circle, the location of sunrise and sunset start to converge in the northern sky, until eventually the sun never sinks below the horizon. Hence, the appearance of the midnight sun.