While many different influences determine local air movement, the large-scale motion of winds over the earth’s surface depends on two factors. The first is differential heating. Equatorial air absorbs more solar energy than air at higher latitudes. Thus, it rises, and cool air from higher latitudes flows under it, while the equatorial air flows towards the poles. Eventually, it cools and sinks continuing as surface winds. Hence, surface wind moves towards the equator at low latitudes and toward the poles at higher latitudes.
Global wind motions are also affected by the Coriolis effect, which influences objects moving within aa rotating system such as the earth. Objects on the earth’s surface move eastward at the same speed as the earth’s rotation – about 1000 miles per hour at the equator, basically zero at the poles. An air mass that has moved north or south from the equator retains this inertial velocity, but the earth it passes over is moving more slowly. Hence, the air is deflected to the east. Winds from the poles towards the equator, on the other hand, have a low velocity compared to the areas they pass over; they are deflected towards the west.
The author is primarily concerned with:
- Summarizing evidence
- Explaining phenomena
- Outlining opposing views
- Offering hypothesis
Answer. (b) This is a global question. The author is describing and explaining observable phenomena. Option (a) would require some statement that the facts mentioned by the author are proof or support for some theory. Only one view is presented in (c), and it is not presented implicitly as a hypothesis.
According to the passage, winds near the equator usually do which of the following?
- Absorb solar energy at an unvarying rate.
- Flow towards the equator near the earth’s surface and away from it at higher latitudes.
- Rush towards the east faster than the earth’s rotation.
- I only
- II only
- I and II only
- I and III only
Answer. (b) Here we have a straight “Explicit Detail” question. Go to the points in the passage at which the behaviour of winds near the equator is described.
Statement II is easy to verify; it rephrases the fourth and sixth sentence of paragraph 1. Statement I and III are easy to rule out because they contain exaggerated ideas. In statement I the word used is ‘unvarying’. Why would the rate be unvarying? It should be at least varying between night and day, and perhaps at different times of the year. In statement III, the word ‘rush’ should stand out; whatever the winds do, they don’t rush out.
The passage suggests that if the Coriolis effect did not exist, high altitude wind near the equator would do which of the following?
- It would not appear to move, because it would flow east at the same speed as the earth.
- It would flow faster towards the west than the earth’s rotations.
- It would directly flow towards north or south from the equator.
- It would remain stationary and mix the warmer air from higher latitudes.
Answer. (c) Here’s a problematic inference question, because the Coriolis effect is itself difficult to understand. If you are not familiar with it, re-read the paragraph that describes it, i.e. the second paragraph.
In paragraph 2, it is explained that the Coriolis effect deflects the winds. So, there was no such effect; the winds would rise and flow away from the equator – either north or south because the equator has two sides.
Other options can be eliminated. Option (a) is tricky. The wind’s speed would match that of the earth, initially, but it leaves out differential heating, which causes the wind to move away from the equator. Option (b) and (c) are contrary to the passage. Winds flowing from the equator are deflected towards the east, and not west. Additionally, the wind cannot remain stationary because of differential heating.
The author would describe global air movements, in comparison with local winds, as:
- Less regular
- Less well understood
- Less interesting
- Less predictable
Answer. (d) This is an inference question. The first sentence specifies that ‘many’ influences determine local winds, while only two determine global air movements. Logically, the interaction of ‘many’ factors would be difficult to predict.
Option (a) is wrong – the drift of the whole passage is that global air movements are highly regular.
Option (b) is beyond the scope of the passage. Global winds seem to be quite well understood, and we do not have any basis for comparison with local winds on this point.
Option (c) would depend on what one is interested in. There is no basis for this option.
What stands in the way of widespread and careful adoption of Genetic Modification (GM) technology is an ‘Intellectual Property Rights’ regime that seeks to create private monopolies for such technologies. If GM technology is largely corporate driven, it aims to maximise profits and that too in the short run.
This is why corporations make significant investments for herbicide-tolerant and pest-resistant crops. Such properties only have a short window, as soon enough; pests and weeds will evolve to overcome such resistance. This suits the corporations. The National Farmers Commission pointed out that priority must be given in GM to the incorporation of genes that can help impart resistance in drought and other stresses.
Which one of the following is the most logical, rational, and crucial message conveyed by the above passage?
- Public research institutions should take the lead in GM technology and prioritise the technology agenda.
- Developing countries should raise this issue in WTO and ensure the abolition of Intellectual Property Rights.
- Private corporations should not be allowed to do agri-business in India, particularly the seed business.
- Present Indian circumstances do not favour cultivation of genetically modified crops.
Answer. (a) According to the passage, option (a) is the most logical, rational, and crucial message conveyed by the passage. GM technology is largely corporate driven which aims to maximise profits and that too in the short run. Moreover, private monopolies for such technology results into vulnerability for farmers. So, public research institution should take the lead in GM technology and prioritise the technology agenda.
On the basis of the above passage, the following assumptions have been made:
I The issue of effects of natural calamities on agriculture is not given due consideration by GM technology companies.
II In the long term, GM technology will not be able to solve agricultural problems arising due to global warming.
Which of the above assumptions is/are valid?
- Only I
- Only II
- Both I and II
- Neither I nor II
Answer. (a) Only assumption I is valid according to the passage. GM technology companies do not consider about the issue of natural calamities on agriculture as they always aim to maximise profit.