CENTO means Central Treaty Organisation

 

Write a short note on the CENTO.

CENTO means Central Treaty Organisation.It was formed in 1955 A.D.It was signed by turkey and Iraq.Later on the USA,England,Iran and Pakistan also joined it.Its main aim was to offer collective defence against Russian attack.

Write a short note on Warsaw pact.

The Warsaw pact was formed in 1955 by Russia,Albania,,Bulgaria,East Germany,Czechoslovakia,Poland and hungary.Its main aim was to defend any attack from western countries.

Write short note on (a) Guided missiles (b) radar.

(a)    Guided missiles The atomic fuel can be dropped at a desired place with the help of electronic radar is called the guided missiles.The electronic missiles travel at the rate of 9200 miles per hour.

(b)   Radar: the radar is an apparatus that can locate a ship or guided missile from a distance of hundreds ofmile even in darkness,mist,fog or rain.The electronic waves that emerge from the radar are sent back when they strike anything and received back by the radar.

How can atomic energy be used for useful purposes?

Atomic energy can be used for useful purposes in driving car,trains,ships,rocket etc.It can also be used in extracting metals from ores and in agricultural purposes in producing unlimited supply of foods.It can also be used in curing diseases and in undertaking space travel.

Mention the chief cause o the rise of national movements in asia after the second world war.

The imperialist countries exploited their colonies politically and economically.The colonies in asia rose national movement after the second world war.Its main reason was that the imperialist countries became weak after the war.

Who was sun yat sen? State briefly his patriotic movement?

Sun yet sen was the chineses leader of the early 20^th century.He organized a political party known as Kuomintang.He organized this party on the lines of Russia communism.He was the founder of Chinese communism

the impact of industrial revolution on society in un industrialist countries

What was the impact of industrial revolution on society in un industrialist countries?

The Industrial Revolution started in Europe in the 18^th century first of all,but it had great impact in un-industrialised century first of all,but it had great impact in un-industrialsed contries of the world of the world in many ways.

(i)                 Before the advent of Industrial Revolution ,the non-industrial countries exported cotton,wollen,silk,indigo etc.but their export was badly affected by the industrial revolution .

(ii)               The Industrial Revolution produced large quantity of quality goods in industrial countries like England,France,Germany etc.They started to export their surplus goods to non industrial countries.In no time these non-industrial countries started  to import commodities instead of exporting them.So,their export suffers a great set-back

(iii)             Various small and cottage industries of the non –industrial countires became unemployed and had to live a poor and miserable life.

(iv)             As a result the worker and craftsmen of the non-industrial countries became unemployed and had to live a poor and miserable life.

(v)               Before the industrial Revolution  many people were engaged in agriculture.But after the industrial Revolution,since there had been mechanised agriculture,these farmer became jobless.So,the life of the farmers became deporable and wretched. On the other hand pressure on land increased.The non-industrial countries became totally mechanised agriculture countires.

(vi)             The good manufactured in non-industrial countries could not compete with those manufactured in  industrial countries in price and quality.The industrial countries imposed heavy duties on the goods imported from non –industrial countries.As a result,they suffered huge losses.

(vii)           The industrial countries forced the forced the farmers of non-industrial countries to sell  their raw material at cheaper rates inorder to earn more profits.This loot was the direct result of the industrial Revolution.

Q6.What were the problem of the newly independent countries at the advent of In dustrial Revolution?

Man’s life has never been stale.It has always been progressive and dynamics.To make progress in all spheres of life is the human nature.The developing countries had to face many probems when they tried to advance in political,economics and social fields.The problem of the newly independent countries of the advent of Industrial Revolution were as follow.

1.Economics problems:-The newly independent countries had to face many economics problem,because they had long been made poor by the exploitation of imperialist powers.They lacked in capital,foreign aid and modern advanced technology for the development of their industries.There were no ample opportunities of employment for them.The problems of good housing and clothing for the ever increasing population became very acute.These countries need todevelop basic and heavy industries to increase their agriculture production in order to feed their teeming population and to provide jobs for them.

2.Social problems: the people of the newly independent countries are not properly educated,because the imperialist countries which dominated them paid no attention to their education.It is quite necessary to educate the people to remove ignorance ,illitarcy,old traditions,superstitions,blind faiths and social evils like the child marriage,purdah system,dowry system,caste systems etc.

3.Political problems: the newly independent countries had to face many political problema also.They ha d to decide the type of government they shoukd established—Parliamentary type of democracy or the presidential type of Democracy or Dictatorship,etc.They should also frame their own foreign politics.They had also to decide which bloc they should join—America bloc,Russian bloc or remained non-aligned.They had to set up an effecient  system of administration and frame adequate laws for the welfare of all the people.

Briefly point out the political changes in the world after the Second World War?

After the second world war,England and France lost all their colonies,which had become independent colonies.Further,they became weak militarily and economically.Instead ,Russia and America became powerful.

Why did England and france become weak militarily and economically after the second world war through they were victorious in the that war

England and France were the main opposing powers in the second world war.So,they suffered a huge loss of life and property.Their industrial centres and cities were destroyed in the war.So,they became weak militarily and economically,though they were victorious in the war.

How did America become the first rate power after the second world war?

Being far away from Europe which  was the center of the second world war,America could save itshelf from the destruction caused by the war.As America helped England and France,she enhanced her influence.So America became the first rate power after the war.

How did Russia increase her honour and prestige after the second world war ?

In the second world war Russia inflicted crushing defeat on her enemies,especially Germany.She expanded her empire to a great exent.So,she increased her prestige and honour after the war.

How did the breakdown of the imperialist countries take place in the world after the second world war?

During the second world war,the imperialist countries of the world fought against one another .As a result ,all of them became weak.These colonies became independent by launching freedom movements.Thus the imperialist countries broke down after the war.

Write a short note on NATO ?

NATO is the abbreviation of the North Atlantic treaty Organisation.It was a treaty concluded in 1949 by France,Belgium,U.K,Italy ,Denmark,Portugal,USA and Canada to prevent the expansion of Russian Communism.

State the main provision of the NATO.

The main provision of the NATO were as follows :-

(i)                 Member countries will render financial help to one another in times of peace.

(ii)               They will solve their disputes through talks.

(iii)             An armed attack against one or more of the members shall be considered as an attack them all.

(iv)             Every member state shall organize its military strength with the help of USA.

What is meant by SEATO ?

SEATO stands for the South East Treaty Organisation.It was formed in 1954.It was a sort of defensive alliance signed by the USA,UK,France,Australia,New Zealand ,Thailand,Philippine and Pakistan to check the expansion of communism.

women effected social revolution in the twentieth century Europe ?

How has the new status for women effected social revolution in the twentieth century  Europe ?

In the twentieth century Europe, the women had equal right as men. So, they took active share in the politics of the continent. Before this time, only men took part in the social revolution. But, in the twentieth century women also took active part in the social revolution. Thus, the new status of women effected the social revolution of Europe.

What are the main defects of capitalism?

The defects of capitalism are as follows: 1. the workers have no right over his work and capital, 2. the workers are exploited by the capitalist, 3. the workers work more hours, but are paid lower wages, 4. the working condition is very bad, 5. they live in slums, 6. they can be dismissed at any time, 7. women and children are made to work, 8. there is lack of equality and justice.

Mention the chief features of socialism.

The chief features of socialism are as follows: 1. the means of production are owned by the society as a whole, 2. the chief aim of production is for the welfare of the society as a whole, 3. there is no exploitation of the workers, 4. it lays emphasis on equality, 5. the natural resources is distributed equally among all citizens.

What were the results of the exploitation of the colonies by the imperialist countries?

The results of the exploitation of the colonies by the imperialist countries were that there were hunger, famine, unemployment in the colonies. The people of the colonies had no good houses to live in, no good food to eat and no good clothes to wear. They were ignorant, illilerate and superstitious.

Bring out the meaning of the Industrial Revolution.

The shifting of the work of manufacturing from homes to the factories is said to be Industrial Revolution. Formerly the work of manufacture was done in cottages. But, in course of time industries have been set up in factories by capitalists. This is what is Industrial Revolution.

Sketch in brief the impact of industrialization on society.

The Industrial Revolution has affected the society in various ways. It transforms the political, economic and social life of the people of a country.

Discuss in brief the impact of Industrial Revolution on politics.

Industrial Revolution produces goods on a large scale. The home markets cannot consume all the manufactured goods. So, the countries where there is industrial revolution have to set up colonies to be markets of their goods. Their industries require huge raw materials. They try to procure the raw materials from their colonies. This is the political impact of Industrial Revolution.

Bring the impact of the Industrial Revolution on the economy of a country.

The Industrial Revolution has great impact on the economy of the industrialized country . It destroys the domestic system of production. On the other hand big factories have been established. It increases the production of goods, and such, increases national income. It then leads to the improvement of the standard of living of the people, growth of agriculture , etc.

Discuss briefly the social impact of the Industrial Revolution.

The Industrial Revolution has great impact on the society. It causes the disappearance of small farmers and appearances of unsatisfactory condition of the factory workers, exploitation of women and children, two classes in the society- capitalists and workers, moral downfall of the society, insanitary condition, etc.

Sketch briefly how the Industrial Revolution brings about moral downfall of the society .

As a result of the Industrial Revolution women have also to work for long hours in factories in order to supplement theirs family income.As aresult,they have no time their of it’s the energy to look after children and household duties.It is difficult for them to maintain their modesty and virtue.

Why is it said that the industrial revolution make the services condition of the worker unsatisfactory ?

In order to make the huge profits the capitalist employers did not keep the factories well ventilated and well lighted.They did not keep the factories neat and clean.Consequently there was un healthy condition in the factories.

Give reason why the industrial Revolution caused the disappearance of small farmers.

As the small framers worked on small farms,they could not maintaine themselves and their families.So,they had to work in the factories in towns.That was why the Industrial Revolution caused the disappearance of small farmers.

Give sa brief account of the economics consequences of the second world war.

Most of the countries of the world were economically ravaged by the second world war.They were initially built by Americans help and hard work of the people.Now,America aithdrew the help.So,the European economics,etc .It recovered and reconstructed the economoy of the community was set up by the France,Germany,Belgium region.As a result these countries made much progress economically.

Presidental Type of Government in the modern democracy

What do you by the Presidental Type of Government in the modern democracy?

In the Presidental Type of Government in the modern democracy, the President is the real head of the government. There is no Prime Minister. The President is directed by the people. The executive is not a part of the legislature. The President and his secretaries are not the members of the legislature. In USA there is such a government.

How is the Prime Minister appointed in the parliamentary Type of Government in the modern democracy?

In the parliamentary Type of Government in the modern democracy the leader of the majority party is appointed the Prime Minister. So, there is proper co-ordination between the legislature and the executive. If he loses majority in the legislature he and his government have to resign.

Discuss briefly the unity form of government in the modern democracy.

In the unitary form of government in the modern democracy all the powers of the state are vested in the Central government. It may be divided into various units to run the administration smoothly, But these units are not independent of the Central Government, but act only as agents.

State the conditions in which a democratic government is federal.

When there is a division of powers between the centre and the units of a democratic government, the state has a federal form of government. Both are independent in their own spheres. In such a form of government an independent judiciary is set up to settle the disputes between the centre and the units. Both the centre and units are not agents of the centre.

What is an authoritarian state? What are its main features?

In an authoritarian state one person or his ruling front is all-in-all, and people have no rights whatsoever. Its main features are absence of political party, absence of freedom for its people, irresponsible government and non-participation of the citizens.

What d o you mean by socialistic state? What are its main features?

The state in which its powers are vested in a large number of people, who work for the welfare of all, is called a socialistic state. Its main features are complete control of the economy by the state, equal treatment to all people, absence of employment, political and economic equality and full government control over the life of the people to remove exploitation.

Describe briefly what a police state is.

The state in which the ruler acts in an autocratic manner and interferes too much in the life of the people is called a police state. In such a state the ruler’s will or order is the law. He himself is above the law. All the power of the state is vested in him.

telephone

What do you mean by telephone? Who invented it?

The apparatus with the help of which a person can talk to another living at a distance known as telephone. A man named Graham Bell invented it.

Who was Marconi? Write a short note on his achievements.

Marconi is the inventor of wireless telegraphy. He invented it in 1899 A.D. Hesucceeded in sending wireless messages across the Pacific Ocean in 1901 A.D.

What is radio? How was it invented?

Radio is a receiving set for sound transmitted by air waves. It was predicted by James Maxwell in 1865 in England. Further improvements were made by Edison.

What do you understand by mass media? What are the main means of mass media?

 The means which help in the formation of public opinion are known as mass media.The main means of mass media are press,radio,television and cinema.

Give an account of the press as one of the means of mass media?

Ans:-Press or newspapers are the most important means of mass media for organizing public opinion.The newspapers give information about the national and international events,various political thoughts and ideas and programmes and policies of the  to form public opinion on various matters.

Describe briefly the importance of radio as a means of mass media?

The radio is the cheapest and the most effective means of communicating ideas on current affairs to the large population of the world.Millions of people daily listen to the latest news of the world through radio.It makes the listener think of what is happening in the world through radioIt teaches its listener think many good ideas and views.So it is highly useful for mass education.

television as an effective medium for education

Give a brief account of the television as an effective medium for education.

On the television screen we can see the live programmes and events of national and international importance. It gives us knowledge about the happening of the world, thoughts and ideas of different people and the problems which man is facing the world. Television also provides effective medium for mass education and entertainment.

Discuss briefly the importance of the cinema as a means of mass media.

On the cinema screen we can listen to the voice of actors and actresses and see their faces and acting as well. It provides a good means of bringing home to the people various social evils and suggesting ways to eradicate them through dramas, stories, etc. in an effective manner. It is one of the very important means of mass media, because a large number of people learn many things from the cinema.

Discuss the impact of mass media on culture.

All the means of mass media occupy a very important place in the development of culture. They promote social and culture contacts between various people of the country and among the people of different countries of the world. The people learn the good features of other cultures and try to reform themselves. The audience or listeners of the mass media learn the dress, style and culture from them. Thus the mass media has great impact on culture.

Name four scientists with their special contributions in medical sciences.

The four scientists with their special contributions in medical sciences are as follows:

1. Alexander Flamming: discovered penicillin.
2. Robert Koch: invented the small-pox injection.
3. Morton and Simpson: introduced anaesthesis.
4. Laster: invented antiseptic surgery.

How has the invention of internal combustion engine led to the development of aviation industry?

The invention of the internal combustion engine at first enabled man to make motor vehicles, cars, buses, etc. Then in the nineteenth century the Wright brothers invented aeroplanes. Thenceforth, the aviation industry came into being. Thus, the invention of the internal combustion engine led to the development of aviation industry.

State the “crowning scientific achievement of the nineteenth century”.

In the nineteenth centur, Dr. Einstein discovered the Theory of Relativity. This theory led to the making of atom bomb. This is the crowning scientific achievement of the nineteenth century.

State briefly the various types of state in the temporary world according to Aristotle.

According to Aristotle states are classified into monarchy, authoritarian rule, aristocracy, socialist state and democracy.

 What is meant by monarchy according to Aristotle?   

According to Aristotle in a monarchy the power of the state is vested with the monarchy, but he rules in the interest of his subjects; but, rules in his own interest.

Define authoritarian state according to Aristotle.

According to Aristotle, the authoritarian state is the state where the autocratic ruler cares nothing for the interest of his subjects; but, rules in his own interest.

What is meant by aristocracy according to Aristotle?

According to Aristotle, in aristocracy, the power of the state is controlled by a few rich and powerful individuals who care for the welfare of the public.

What is the definition of the democratic government according to Dr. Lincoln?

According to Dr.Lincoln, a democratic government is the government of the people, by the people, for the people.

Enumerate the main features of a democratic government .

The main features of a democratic government are political equality, freedom, responsible government and active participation of citizens.

What is a democratic state in the contemporary period?

Democratic government in the contemporary period is the government in which the citizens have the right to participate in the government process and in making important decisions for the welfare of the whole society. A democratic government must fulfil responsibility towards the citizens.

What do you mean by Responsible Government in a democratic government as a define by Dr.Lincoln?

A democratic government is always responsible to the people, who have the right to change it during elections. This is just like what we are doing in India.

Explain briefly the Parliamentary Type of Government in a democratic government of today.

In a democratic government of today we can have a Parliamentary Type of Government . For example, India and England have this type of government. In a Parliamentary Type of Government the president is only the nominal or constitutional head. The real head of the government is not directly elected by the people, but he is elected by the an electoral college.

science has become a means of destruction

How far is correct to say that science has become a means of destruction?

While the development of science and technology is a boon, these are also a curse to mankind. They are really very powerful. It they were used for useful puuposes, they become a boon. But , if they are used for destructive purposes they are indeed a great curse, for they may destroy the whole civilization and can sweep away mankind from the surface of the globe.

Why are we so much afraid of war in the modern time?

In the world of to-day vastly destructive weapons such as the atom bomb, etc. have been invented. It they are used our whole civilization, even the mankind can be destroyed altogether . So, we are so much afraid of wad these days.

How has the span of man’s life been increased these days?

Medical Science is advancing rapidly. Scientists have invented various medicines to prevent or cure diseases. As a result many diseases have disappeared and many others are less prevalent . So , the span of man’s life has been increased.

How is x-ray useful in the treatment of diseases ?

X-ray is an equivalent to take the pictures of the interior parts of the body. It is useful to diagnose different diseases and to give proper treatment of the diseases . Thus X-ray is very useful in the treatment of diseases.

Mention three medicines which had been invented in the 20^th century. Also mention the diseases  they can cure.

The three chief medicines invented in the 20^th century are sulpha drugs, penicillin and antibiotics. Penicillin is used in the treatment of different infections. The sulfa drug is used in the treatment of different infections. Antibiotics are very effective in the treatment of eye infections, ulcer, meningitis, T.B., dysentery  and bladder and kidney infections.

In which century were vitamins discovered? Mention its various uses.

Vitamins were discovered in the 20^th century. It is used to maintain health, to tackle the problems of mal-nutrition and to cure the diseases like rickets, beri-beri, pellagra, etc.

Who were Picasso and Matisse? Mention their prominence.

Picasso and Matisse were the prominent figures in the modern art of painting. Picasso used the method of abstract then resembled into  

atomic power station of India

Mention some of the atomic power station of India.Why did India set up these stations?

Ans:- Some of the Atomic Power Station of India are at Tarapur,Kota,Kalpakkam,Narora etc.India is determined to use atomic energy for peaceful purposes such as for agriculture for medical purposes and for exracting minerals from soil etc.

How have science and technology developed transport?

Science and technology have greatly developed the means of transport.With the help of science and technology the engineers have made automobiles such as motor,car,trucks,buses and railway trains.They have made aeroplanes and rocket also with the help of science and technology.

Write a short note on the usefulness of automobiles to mankind.

Automobiles are good means of transport.These have shortened distances.these have transported goods from one place to another.Aeroplanes have provided the facility for faster travel.Indeed they have shrunk the distance  between different places of the world.

What is communication ? How has science and technology developed communication?

Communication means the sending of message from one place to another.Science and technology haved developed the means of communication in the 20^th century to a great extent.The mean of communication are post and telegraph,telephone,wireless,radio,television, etc.Through these mean we can contact with other people quite far away from us.

Second Industrial Revolution

What do you mean by the Second Industrial Revolution ? write briefly about it.

The great advancement of science and technology in the 20^th century is known as the Second Industrial Revolution. It has contributed a lot towards industrial progress. The engineers discovered various machines and tools for the manufacture of goods in all industries. This revolution brought about large quantities of quality goods.

In which century did plastic industry make great progress? What is the usefulness of plastic industry in our daily life?

Plastic industry made great progress in the 20^th century. Various things of our daily life are made of plastic. These things are cheap, durable, light in weight, unbreakable and bad conductor of heat. Plastic utensils are also very useful for these qualities. New fabrics like nylon and orlon have been developed from plastic. These fibres, are fine, strong and durable. They are superior in quality, light in weight and easy to wash.

How is hydro-electricity generated? Point out the usefulness of hydro-electricity.

Hydro-electricity is generated by constructing dams across rivers. It has greatly developed iron and steel industry. This industry has helped a lot in manufacturing big machines, cars, motors, trucks, tractors, railway engines, aeroplanes, press machines, etc. These big machines have played a significant role in the development of basic and heavy industries.

What are the new source of energy? How have they benefited us?

The new sources of energy are coal, mineral oil, hydro-electricity and atomic energy. Before these were discovered the sources of energy were animals. We use these new sources of energy in heating, cooking, and in driving vehicles and in factories.

Discuss the uses of coal as a source of  energy.

Coal is a conventional source of power. It is also an industrial raw material. It is used to convert water into steam which was the basis of Industrial Revolution. It is now used in steam engines. Thermal power is generated from turbines by using the steam produced by coal. Coal is thus permanent source of electricity.

Give a brief account  of mineral oil.

Mineral oil is highly inflammable. It is used in the internal combustion engines. Mineral oil is refined as diesel, kerosene, petrol, aviation spirit, etc. It provided motive power for automobiles, aeroplanes, ships, etc.

How is hydro-electricity generated?

Hydro-electricity is generated from turbines by the use of running water. Big dams are built across rivers and water is stored in large reservoirs. The water is made to fall from a great height. The turbines are made to turn by this running water to produce electricity.

How is atomic energy generated?

Atomic energy is generated by splitting nuclear substances, such as atoms of uranium, thorium, or beryllium under controlled conditions. When splitting these atoms a lot of energy is given out. This is what is called atomic energy.

State briefly how atomic energy can be used.

Atomic energy can be used for both destructive and constructive purposes. It is so forceful that it is vastly destructive. Only two atom bombs could destroy two big cities of Japan. It can also be used for constructive purposes. It can be used to generate electricity and treat diseases.

science and technology during the fourth decade of 20th century (1930-40)

Q.Point out the advancement in science and technology during the fourth decade of 20^th century (1930-40)

Ans:=Television was invented in 1936 by Baired. It is an instrument images by the help of telegraphy. Gas turbine engine was also invented during this period. Hydroelectricity began to be produced by building huge dams. Newsfabrics like nylon, rayon and orlon were also developed by scientists. Muller discovered the insecticide like D.D.T in 1940.

Q.Sketch in brief the advancement in science and technology in the fifth decade of the century.

Ans:=During the fifth decade ot the 20^th century Sir Alexander Flemming of England invented penicillin, which is now used in the treatment of many diseases. Scientist,were also able to generate Atomic or Nuclear Energy during this period.The Americans designed the atomic bomb in 1945 and dropped and destroyed the two cities of japan,Hiroshima and Nagasakhi during this period.The aeroplanes faster than sound were manufactured in 1947.This period also saw the construction of transmitters and electric computers.

Q.Narrate briefly the story of the conquest of space for the first time in the world.

Ans:-The work of the conquest of the space started in 1935.The first rocket,’Sputnik’ was launced by Russia in 1957.From this time onwards the world entered the space age.Yuri Gagarin of Russia was the first man who flew into space in 1961.The USA landed on the moon first at all in 1961 A.D. Communication satellites orbiting the earth began to transmit T.V. programmes.

HISTORY

How did the First World War effect changes in Brazil?

The First World War brought many changes in Brazil. The autocratic rule in the country ended with the end of the war. Instead, a democratic form of government was set up in the country. Agriculture, trade and commerce also made a progress in Brazil.

Show, with four instances, how the anti colonial movement after the Second World War caused the contraction of Europe.

After the Second World War there were anti-colonial movements in the World. Such anti-colonial movements arose in Syria, India, Burma, Indonesia, etc. As a result of these movements many countries of Europe lost their colonies in Asia, Africa, etc. As a result contraction took place in Europe.

Give an account of the family system in India in the eighteenth century.

In the eighteenth century, there was the patriarchal family system in India. Under this system father is the head of the family. His will was supreme in the household affairs of the family. His word was final in matters of matrimony. Only males had the right to inherit property.

State four practical achievements of the United Nations.

The four practical achievements of the United Nations are as follows: 1) It has stopped the war in Korea ,2) It has solved the problem of Indo-China, 3) The U.N. has compromised the conflict in Palestine and 4) It has ended the power Blocs of the world, hostile to one another.

Why did the great majority of Europeans want democracy after the Second World War ?

The Europeans had experienced the rude administration of the Fancist countries of Germany and Italy just before the Second World War. They felt acid test of the one man rule. So, they wanted to shift the power of a state from dictator to the Europeans wanted democracy.

 In what ways did young people begin to show their contempt for old values of life in the contemporary world?

In the contemporary world, the young people showed their contempt for old values of life. Formally life was almost without value, because political right was defined to them. Now the young people came to know what socialism is. Formally life was quite dependent on the rule of one or few men. Thus, values of life was lost for them. So, the young people showed contempt for these.

Briefly sketch the life before scientific and technical advancement.

Before the advancement of science and technology, the life of man was not comfortable. People did not enjoy the facilities of life such as electricity, electric fans, radio, televisions, etc. They lighted their houses with Kerosine lamps. They used wood or coal for heating and cooking.

Mention the chief causes of the progress of science and technology in the 20^th century.

In the 20^th century the governments came to know the importance of science and technology. They, therefore, encouraged the research works and scientific projects by giving financial help. Many wealthy persons also started research works. The large manufacturing industries also started research works in various industries. With all these factors there was progress in science and technology in the 20^th century.

State briefly the scientific advancement in the 20^th century in the field of chemistry.

The study in chemistry gave a vast store of information in the 20^th century. Many diseases were treated with the help of chemicals.

What advancement of science and technology was made during the second decade of the 20^th century?

During the second decade of the 20^th century (1910-1920) radio and wireless communication was invented. Railway vehicles were also introduced during this period in large numbers. Many big canals including the 50 miles long Panama canal was also dug during this period.