IGNOU FST CHAPTER 20 Q1

Q)How has the application of scientific knowledge improved agriculture in the arid zones dry lands and hilly regions of the country?
Ans)In the arid zone there is considerable scope for growing fruit trees like ber and pomegranate and fuel wood yielding trees like Acacia (Kikar), Prosopis (Mosquite) and Eucalyptus (Safeda). In such areas, large scale planting of shelter belts will minimize soil erosion  caused by wind. It will also help in the establishment of pastures and grazing lands. Later on this land can be used for growing pearlmillet and mungbean.
Since water is a limiting factor in drylands, as much run off as posssible should be collected in community owned ponds, so that the crops can be gived life saving irrigation. In dry lands with red soil, deep ploughing helps in conserving water. In black soils, sowing two crops at a  time is possible with surface drainage and good water management.Leaves and crop management, when mixed with soil improve its texture and water holding capacity. If crops like pigeonpea and castor have deep roots, are cultivated in these regions, the physical condition of the soil improves further, as the roots of these crops add organic matter.Now that varieties of sorghum, millets, sunflower, safflower, mustard, groundnut various pulses and cotton are available which grow within a shorter time and can withstand scarcity of water, it is possible to diversify what grows in the dry lands. A variety of crops and cropping patterns allow the farmer to make a proper choice of what to grow in different climate and soil types.There is a solution to the agricultural problem of the hilly regions. The upper regions of the hills are devoted to forestry. The next zone is developed for growing fruit trees, perennial fodder grass and legumes. The roots of legumes fix nitrogen and improve the soil. In the third zone, a mix of crops are raised on terraces constructed with low cost implements. Earthen dams are constructed with locally available material. The collect enough water to be utilized for irrigation and fish culture. Polutry, piggery, bee-keeping mushroom cultivation and related activities create a self sustaining, complete farming system that perfectly blends with the ecosystem.

IGNOU FST CHAPTER 10 Q1

Q)Elucidate the astronomical methods that have provided insights about the universe.

Ans)”Now my own suspicion is that the universe is not only queerer than we can suppose but it is queerer than we can suppose. This remark of Haldane, a famous scientist, reflects, in a way what we feel about this subject. The universe is rather a difficult subject to study. We cannot bring it to the laboratory  to carry out experiments on it. We cannot compare it with any other universe this is the only universe we have. And finally we are a part of it. We can study it only from within. We cannot go out of it and look at it from the outside. So how do we study it. It is here that the scientific method comes to our aid. The easiest method of studying light from a cosmic object is to collect it through a telescope and record it on a photographic plate. Photographic films are exposed for a long period of time-sometimes night after night- to the light being collected by a telescope aimed at distant stars. Since the earth rotates on its axis, the stars appear to move in the sky. The telescope is rotated following the daily movement of stars at which it is aimed. Thus, its movement is synchronized with the movement of the stars being studied, stars too faint for the human eye slowly begin to register on the plate. This method of collecting and investigating light from the cosmos is called optical astronomy. As of today a huge optical telescope called the Hubble space telelscope after Edwin Hubble is in orbit around the earth. Several large telescopes are stationed in Hawaii, Australia Chile Russia UK etc. Many smaller telescopes scan the skies every night adding to our knowledge of the cosmos. The fact that stars emit radiowaves was discovered accidentally in 1932 by a young engineer Karl Jansky. He was trying to find the source of noise in a transatlantic telephone link. He make an experimental radio receiver set to study this problem. To his surpise he found that the disturbance was due to the rasio waves coming from  the milky way galaxy. This was the beginning of radio astronomy, i.e. the study of cosmic objects through radiowaves emitted by them. The radio telescope, a basic tool of radio astronomy, collects radiations from space in the radio wave region one of the largest radio telescope in the world was designed and set up by Indian astronomers at Ootacamund. The other radio telescope, a basic tool of radio astronomy are stationed in Gulamrg, Ahemdabad, Bangalore. With the coming of the spaceage, observatories equipped with telescopes and ceramics could be placed right in space, beyond the earth’s atmosphere. An observatory in space may be in the form of an orbiting satellite like the Unamanned Orbitting solar observatories, Orbitting Astronomical Observatory, Skylab, Einstein Observatory, IRAS(Infra Red Astronomy Satellite) and many others. Instruments are also put abroad high flying ballons, rockets and aircrasts to record observations. These observations can record radiation from a cosmic object in the regions of the spectrum such as the IR,UV,gamma rays and X-rays that do not penetrate the Earth’s atmosphere.AS space research came of age it became possible to send spacecrafts to other planets and even land men on the moon. These ventures also provided a rich stock of information about the solar system. For instance, astronauts of the Apollo mission to the moon in the 1970’s bought back lunar rocks and soil samples, photographs of the lunar surface and left several instruments there for further study. We have been able to send space probes, across the solar System to know about our planetary neighbours. Space probes have visited a number of planets and a host of their moons, and successfully landed on the surfaces of Mars and Venus.

IGNOU FST CHAPTER 12 Q1

Q)Discuss the systems view of life.

Ans)The characteristics which we recognize as life, are in fact an expression of the coordinated working of various parts in an organism. Various  parts in an organism, whether plant or animal are not haphazardly put together but are organized into systems. A system is a set of some specific inter-related parts which are organized as one unit for some purpose. The parts work together and the entire combination forms one unit. A car producing company, which is organized to produce tronaport vehicles can be viewed as a system too. For the effective functioning of the company all of its parts, such as the department that purchases raw materials, the factory , the management and the sales department must work in a unison. An animal or a plant is also made up of numerous parts which define a well defined system. For example in an animal body, the parts concerned with the intake of food and digesting it, the bones are arranges as a skeleton to support the body, the heart circulating blood to different parts of the body through arteries and veins and the brain receiving signals and giving orders of various kinds together compose the system. The assemblage of all plants and animals and in and environment provided by each other as well as by the land, air and water works collectively. The way these diverse forms of life depend on each other makes one imagine this planet as a huge system. Looking at it in another way, the life and environment of the earth are a well coordinated system, within which there are subsystems like individual organisms. And within each of these sub systems , a single plant or animal, one would find a complex multicellular system. Similarly, industrial, agricultural or educational systems can be visualized as the sub-systems in the society. Organic systems maintain themselves in a given composite form and function. For example a cat remains a cat, it prowls for food, it may lat kittens, but its internal system matches on the basis of physical principles with stability. How is this stability maintained by a system? Let us take a specific example; how does a man or a woman maintain this internal stability while the environment around them changes. For instance how do they maintain a fixed temperature of thirty seven degrees, or the composition of their blood or blood pressure? It has been found that all organisms possess a kind of information and control network which directs them to adjust to various kinds of situations of survival. E.g. of you touch a snail, it withdraws into its shell. This is a kind of information and control device for protecting its life. If you sit in the sun and you feel hot, a signal which is internally generated causes perspiration and produces cooling by evaporation of sweat. This is another example of information  and control for maintain a fixed body temperature.

IGNOU FST CHAPTER 17 Q1

Q)Describe the various renewable resources of energy that have the potential to fulfill the needs of the society.

Ans)Solar Energy

The energy we get from the fossil fuels like coal, is in reality sun’s energy, trapped in them millions of years ago plants make their food and grow because they use solar energy for photosynthesis. Millions of years ago, huge forests got buried in the earth’s crust and under great pressure and temperature, they were converted into coal or oil. Hence coal and oil are called fossil fuels. Solar energy is the great source for production of vegetation which serves as food and fuel for us.

Wind Energy

Like solar energy, wind flow can also be harnesses to obtain mechanical energy for fetching water from the wells or from rivers. Once the windmill is turning due to the force of the wind, it may as well run a generator to get electrical energy. In the coastal and hilly regions, where wind blows at high speed, windmill can be used for the supply of electricity to a small town. Windmills have been used since long in many countries, but in India they have been only recently introduced.

Wave and Tidal Energy

Waves and tides are another source of energy which is perpetual and can be converted into electric energy, particularly where sea water can move into a narrow cut, such as is provided naturally, where rivers flow into the sea. Energy carried by water has also been widely used in India’s hilly regions, since a wheel with pedals can be made to run when it is put in a fast flowing stream. Flour mills of small size bult on this principle were used in Kashmir for long time. In fact, large “hydroelectric” power stations work on the same principle. A natural or artificial water fall is made to turn a modern kind of pedal wheel, called a turbine,  which rotates and causes electricity to be generated.

Geothermal Energy

Hot water superheated steam of hot springs are a natural phenomenon and be used to genenerate electricity. In our country there are 46 hydrothermal areas where the temperature of the spring water exceeds 150⁰C. These hot springs can be used to generate electricity for heating homes or glass houses to grow vegetables.

Atomic Energy

In view of the fast depletion of the non-renewable resources like coal and petroleum and because of pollution  which power stations burning coal cause, there has been a move to use other means of obtaining energy. Since the energy of the atom had already been unleashed in the form of a bomb, efforts were made to release atomic energy in a controlled manner. The device used for this purpose is called an atomic reactor. Nuclear reactors produce heat which is commonly used to raise steam, which rotates turbines and generators of electric power. It is estimated that 1 kg of natural uranium, written as U²³, generates energy equal to that produced by 35,000 kg of coal. Thus production of energy from nuclear fuel like uranium is efficient, and since great loads of coal or diesel are not consumed daily, this energy is convenient.

IGNOU FST CHAPTER 3 Q2

Q)In the Iron age medicine developed as a science in India and Greece, but reasons for developments were different Mention one reason for development of medicine in these two countries.
Ans)The Carakas and the Susutras in India were roaming physicians who went about healing ordinary rural folk and fostered democratic thinking and world views. Greek medicine on the other hand could continue its older traditions because of the suport it received from aristocracy.

IGNOU FST CHAPTER 3 Q1

Q)Discuss the developments in the areas of astronomy and mathematics, chemistry, botany and zoology during the Bronze Age
Ans)Chemistry
The level of chemical knowledge and practices in the newly ordered society is reflected in the pottery iron tools and glass objects found at various iron age sites.By the fourth or the fifth century B.C. the Indian metalworkers had attained a high degree of perfection in the techniques of producing iron and steel. Glass objects unearthed in over 30 sites indicate that the production of sites came to be known over the end of this period. Ceramic bowls, dishes, lids and carinated jars dated from about fifth century B.C. to the second century B.C. were also found in these sites. Fermented methods dyeing techniques, the preparation and use of a number of chemicals and color pigments were well known.
Botany
In the Bronze and Iron ages agriculture became the principal mode of production in all lands. It is thus not surprising that in India, botany and elementary plant physiology developed with the advances made in medicine also helped these sciences.
Zoology
The domestication of animals like horses and elephants and their use in warfare necessitated the study of their anatomy and physiology. A survey of vedic literature revealed that more than 260 animals had been known at that time. Classification of animals and study of their dietary values had been attempted. Human physiology had also been studied. post vedic literature also contains names of animals and a avast storehouse of observations on their natural history. These observations may have simulated their later thoughts and concepts about classification , heredity, embryology etc.
Astronomy and Mathematics
Much of the work in astronomy in the iron age is merely a detailed or expanded version of the astronomical knowledge already found in the rigveda. Astronomy later degenerated into astrology in the later years of this period. Sulvasutras show a fairly high level of knowledge of geometry. Arithmetic was equally well developed. Numbers in multiples of 10 going upto as high powers of 10 as 10¹²(one million million) were known and used. All arithmetic operations on numbers were well known. Sulvasutras contain several instances of addition subtraction multiplication division and squaring of fractions, quadratic equations indeterminite equations, permutation and combination also appear in the sulvasutras.