Axiom , Postulates and Theorems :-

Axioms are the general statements, postulates are the axioms relating to a particular field. (2) Statements : A sentence which is either true or false but not both, is called a statement. eg. (i) 4+9=6 it is a false...

Coefficients

In the polynomial , coefficient of  respectively and we also say that +1 is the constant term in it. Degree of a polynomial in one variable : In case of a polynomial in one variable the highest power of the variable...

Variables

A symbol which may be assigned different numerical values is known as variable. Example :C - circumference of circle                   ...

Polynomials

An algebraic expression in which the variables involved have only non-negative integral powers is called a polynomial. (i) is a polynomial in variable x. (ii)  is an expression but not a polynomial. Polynomials are...

Algebraic expressions

A combination of constants and variables connected by some or all of the operations +, -, X and  is known as algebraic expression. Example : et...

Variables

A symbol which may be assigned different numerical values is known as variable. Example :C - circumference of circle                   ...

Constants

: A symbol having a fixed numerical value is called a constant. Example : 7, 3, -2, 3/7, etc. are all constan...

Axiom , Postulates and Theorems :-

Axioms are the general statements, postulates are the axioms relating to a particular field. (2) Statements : A sentence which is either true or false but not both, is called a statement. eg. (i) 4+9=6 it is a false...

Types of Angles

(1)Acute angle - An acute angle measure between 00 and 900. (2)Right angle - A right angle is exactly equal to 900. (3)Obtuse angle - An angle greater than 900 but less than 1800. (4)Straight angle - A straight angle is...

Types of Angles

(1)Acute angle - An acute angle measure between 00 and 900. (2)Right angle - A right angle is exactly equal to 900. (3)Obtuse angle - An angle greater than 900 but less than 1800. (4)Straight angle - A straight angle is...

Name three famous writers and philosophers who influenced the French- Revolution. What were their ideas?

Ans. 1. Jean Jacques Rousseau – a French Swiss philosopher. His main idea was – man is naturally good and that society of civilisation makes man anxious and unhappy. 2.  Mirabeau – he brought about a journal and delivered...

Discuss the participation of women in political clubs, their activities and demands.

Ans. 1-Women played important role regarding various activities.  In order to discuss and voice their interests women started their own political clubs and newspapers. About sixty women’s clubs came up in different...

Describe the importance of Declaration of the Right of Man in France.

Ans 1-The Declaration of the Right of Man in France was a landmark decision in the history of France. 2- The constitution began with a declaration of the Rights of Man and Citizen. Rights such as the right to life, freedom...

What landmark decisions were taken by the National Assembly led by the Third Estate on 4th August, 1789.

Ans. 1- Louis XVI finally accorded recognition to the National Assembly and accepted theprinciple that his powers would be checked by a constitution. 2- On 4 August 1789, the Assembly passed a decree abolishing the feudal...

Describe the causes for the fall of Jacobin government in France.

Ans. (i) The Jacobin government in France was based on extreme measures. The period from 1793-1794 is referred to as the reign of terror. Robespierre followed a policy of severe Control and punishment. (ii)All those he...

write short note on Jacobins?

Ans. 1- They got their name from the former convent of St. Jacob in Paris. 2-They belonged to the less prosperous sections of the society. 3-They included small shopkeepers, artisans such as shoemakers, pastry cooks,...

Name three famous writers and philosophers who influenced the French- Revolution. What were their ideas?

Ans. 1. Jean Jacques Rousseau – a French Swiss philosopher. His main idea was – man is naturally good and that society of civilisation makes man anxious and unhappy. 2.  Mirabeau – he brought about a journal and delivered...

Who formed the National Assembly? On what date is ‘Bastille Day’ celebrated and why?

Ans. 1-The representatives of the Third Estate assembled at Versailles on 20 June and declared themselves a National Assembly 2-The Bastille Day is celebrated on 14th July every year because on this day the unruly Paris...

Who was the people who comprised the Third Estate? Who paid the taxes and to whom?

Ans 1-The people who comprised the Third Estate were big businessmen, merchants, lawyers, peasants, artisans, small peasants, landless labourers and servants. 2- These were 95 per cent of the population. They had to pay...

Explain what a revolution is. In what way did the French Revolution mean different things to different people?

Ans It is an attempt by a large number of people to change the government of a country, especially by violent action. 1. The Third Estate comprising the common men benefitted from the Revolution. The clergy and nobility...

Why did slavery begin and why was it abolished in French colonies?

Ans 1-.The slave trade began in the 17th century. The colonies in the Caribbean – Martinique, Guadeloupe and San Domingo – were important Suppliers of commodities. 2- But the reluctance of Europeans to go and work in distant...

What was ‘natural and inalienable rights’?

Ans1-.The constitution began with a Declaration of the Rights of Man and Citizens 2- Rights such as the right to life, freedom of speech, freedom of opinion, equality before law were established as ‘natural and inalienable...

Describe how the new political system of constitutional monarchy worked in France.

Ans The constitution of 1791 vested the power to make laws in the National Assembly, which was indirectly elected. That is, 1. Citizens voted for a group of electors, who in turn chose the Assembly. Not all citizens, however,...

Describe the incidents that led to the storming of the Bastille.

Ans. 1- National Assembly was busy at Versailles drafting a constitution; the rest of France was seething with turmoil. 2- A severe winter had meant a bad harvest, the price of bread rose. Often bakers exploited the situation...

What was the system of voting in the Estates General? What change did the Third Estate want in this system?

Ans. Voting in the Estates General in the past had been conducted 1. According to the principle that each estate had one vote. 2. Members of the Third Estate demanded that voting must now be conducted by the assembly...

what was the subsistence crisis? Why did it occur in France during the Old Regime?

Ans. 1- The population of France was on the rise. It rose from 23 million in 1715 to 28 million in 1789.This led to increase in the demand for food grains. 2-The production of food grains could not keep pace with the demand...

NAPOLEON

In 1804, Napoleon crowned himself emperor of France. He set out to conquer neighbouring European countries, dispossessing dynasties and creating kingdoms where he placed members of his family. He saw his role as a moderniser...

WOMEN’S REVOLUTION

From the very beginning, women were active participants in the events which brought about so many changes in the French society. Most women of the third estate had to work for a living.Their wages were lower than those of...

THE OUTBREAK OF THE FRENCH REVOLUTION

The French Revolution went through various stages. When Louis XVI became king of France in1774, he inherited a treasury which was empty. There was growing discontent within the society of the Old Regime. 1789, Convocation...

Time Line: The French Revolution

1770s-1780s — Economic decline: French Government in deep debt. 1788-1789 — Bad harvest, high prices, food riots 1789, May 5 — Estates-General convened, demands reforms. 1789, July 14 — National Assembly formed. Bastille...

Why is photosynthesis considered an endothermic reaction?

In the photosynthesis  process light energy from sunlight is absorbed to produce oxygen and glucose from carbon-dioxide and water in the presence of chlorophyll, and the process in which energy is absorbed is called...

On what basis is a chemical equation balanced?

A chemical equation is balanced on the basis of law of conservation of mass. According to this law mass can neither be created nor be destroyed....

List any four observations that help us to determine whether a chemical reaction has taken place ?

(i) Change in state (ii) Change in colour (iii) Evolution of a gas (iv) Change in temperature....

What does symbol (aq) represent in a chemical equation?

The symbol (aq) represents aqueous solution. When it is written after a chemical formula in a chemical equation, it represents that the element or compound is a aqueous solution i.e water is added into the solutio...

Which one is a chemical change—rusting of iron or melting of iron?

Rusting of iro...

A magnesium ribbon should be cleaned before burning it in air. Why?

It should be cleaned to remove the dust particles and its oxides that may be present on  its upper surface, so that it comes directly in contact with air....

State one difference between a physical change and a chemical change?

In a physical change, no new substance is formed while in a chemical change, a new substance is formed....

Is burning of a candle wax a physical change or a chemical change?

Chemical change(candle wax is a hydrocarbon,which burns to produce co2,soot etc.)...

What is meant by a chemical reaction?

A chemical reaction is a process that leads to the transformation of one set of chemical substances to another. Example rusting of iron, burning of coal and digestion of food etc. ...

Describe the legacy of the French Revolution for the peoples of the world during the nineteenth and twentieth centuries.

Sol.     The ideas of liberty and democratic rights were the most important legacy of the French Revolution. These spread from France to the rest of Europe during the nineteenth century, where feudal...

Which groups of French society benefited from the revolution? Which groups were forced to relinquish power? Which sections of society would have been disappointed with the outcome of the revolution?

Sol.     Peasants and artisans of French society benefited from the revolution. Clergy, nobles and church had to relinquish power. It is obvious that those who had to forego power and privileges would...

Describe the circumstances leading to the outbreak of revolutionary protest in France.

Sol.     Following are some of the causes which had a cumulative effect to result in revolution in France: (a) The war with Britain for an independent America: This war led to mounting debt on the French...

The Island groups of India

Sol.     The Lakshadweep Islands are in the Arabian Sea. Its area is 32 sq km. The administrative headquarters of Lakshadweep is at Kavaratti island. This group of islands is rich in terms of biodiversity. The...

The Central Highlands

Sol.    The Central Highlands lies to the north of the Narmada river. It covers the major portion of the Malwa plateau. The rivers in this region flow from southwest to northeast; which indicates the slope...

Write short notes on the following: (i) The Indian Desert

Sol.      The Indian desert lies towards the western margins of the Aravali Hills. This region gets scanty rainfall which is less than 150 mm in a year. Hence they climate is arid and vegetation...

Which are the major physiographical divisions of India? Contrast the relief of the Himalayan region with that of the Northern Plains of India.

Sol.      The landmass of India can be divided into following major physiographic divisions:             (a) The Himalayan Mountains            ...

Describe how the Himalayas were formed.

Sol.      The Indian Peninsula drifted towards the north and finally collided with the much larger Eurasian Plate. As a result of this collision, the sedimentary rocks which were accumulated in the...

Bhangar and Khadar

Sol.     Bhangar is the largest part of the Northern Plains and is formed by the oldest alluvium. On the other hand, Khadar is the younger deposit of alluviu...

Distinguish between (i) Converging and diverging tectonic plates

Sol.     The converging tectonic plates move away from each other, while diverging plates move towards each othe...

Name the island group of India having coral origin.

Sol.     Lakshadwe...

Which plateau lies between the Aravali and the Vindhyan ranges?

Sol.    The Malwa plateau lies between the Aravali and the Vindhyan range...

Name the three major divisions of the Himalayas from north to south.

Sol.     Three major division of the Himalayas from north to south are:  (a) The Great or Inner Himalaya (b) The Lesser Himalaya or Himachal (c) The Shiwali...

What is bhabar?

Sol.      After descending from the mountains, the rivers deposit pebbles in a narrow belt. The width of this belt is about 8 to 16 km and it lies parallel to the Shiwaliks. This region is known...

Which continents of today were part of the Gondwana land?

Sol.    The Malwa plateau lies between the Aravali and the Vindhyan range...

What are tectonic plates?

Sol.    The crust of the earth is not in the form of a continuous plate rather in the form of broken pieces. These pieces of the earth’s crust are called tectonic plate...

The central location of India at the head of the Indian Ocean is considered of great significance. Why?

Sol.      The trans Indian Ocean routes which connect the countries of Europe in the West and the countries of East Asia provide a strategic central location to Indi...

The sun rises two hours earlier in Arunachal Pradesh as compared to Gujarat in the west but the watches show the same time. How does this happen?

Sol.      The latitudinal and longitudinal extent of the mainland is about 30°. Despite this fact, the east-west extent appears to be smaller than the north-south extent. From Gujarat to Arunachal...

Which island group of India lies to its south-east?

Sol.       (i) Lakshadweep islands.              (ii) Russia, Canada , USA,         China,...

Name the countries which are larger then India.

Sol.      Australia, Brazil, Canada, China, Russia and U...

Name the group of islands lying in the Arabian sea.

Sol.       LAkshadweep...

Define melting point and Boiling point ?

Melting point : It is the temperature at which a solid changes to liquid. Different Higher melting point means large force of attraction between particles. Boiling point : It is the temperature at which a liquid changes...

Define latent heat of Fusion, is it same as latent heat of vaporization ? Comment ?

Latent heat of fusion is the amount of heat required to convert 1 kg of solid at its melting point to liquid at same temperature. Latent heat of vaporization It is the amount of heat required to convert 1 kg of liquid at...

What are the properties of gases ?

(i) Gases can be compressed easily (ii) Gases neither have fixed shape nor fixed volume (iii) Gases have very low densities (iv) Gases have fluidity (v) Particles of gases have very large spacing and very weak attraction...

Define the term inter - conversion of matter ?

The phenomenon of change of one state of matter into another an back to the original state is called inter - conversion of matte...

What is meant by physical property of substance ? Name the important physical property ?

Physical properties : Those properties of a substance which we can observed without altering the identity of the state. - Colour - Smell -Density - Solubicity - Melting point and boiling point - Conductivi...

Define density and write down its S.I unit ?

Density means mass per unit volume Density = mass / volume Particles in solids are very closely packed so they have high density. In gases, there is plenty of spaces between particles due to which density is low. S.I unit...

Why is oxygen called as gas ? Give two reasons ?

(i) Oxygen neither has a fixed shape nor a fixed volume. (ii) Oxygen exerts pressure due to the collisions of the molecules on the walls of the containing vesse...

Give two reasons to justify - (a) Water at room temperature is a liquid (b) An Iron almirah is a solid at room temperature.

(a) Water is a liquid because of the following two reasons : (i) liquids do not have a fixed shape : They take the shape of the container in which they are kept (ii) Liquids have a fixed volume : Take 100 ml of water in...

Rearrange the following substance in increasing order of forces of attraction between the particles ? Oxygen , Water & Sugar ?

The forces of attraction are the strongest in solids, followed by liquids and weakest in gases Solids > liquids ? gases Therefore, the force of attraction between particles increases in the order Oxygen < Water <...

Comment upon the following : Rigidity, Compressibility, fluidity, Density, shape and volume

Compressibility :  It means tendency to decrease volume when some outside force is applied. Spacing between particles of  gases can be decreased so gases have high compressibility. But spacing between particles...

Liquids generally have lower density as compared to solids. But you must have observed that ice floats on water. Find out why ?

Ice has cage like structure, i.e, when water freezes to form ice, a number of empty spaces are created. As a result, volume increases for the same mass of water. of we can say that density of ice is lower than that of water...

Write down three application of compressed gas ?

(i) Compressed helium gas is filled in air balloons (ii) Compressed natural gas (CNG) is filled in cylinders which are used in vehicles. (iii) Liquefied petroleum gas (LPG) is filled in cylinders which are used for cook...

Name the two gases which are supplied in compressed form ?

The two gases which are supplied in compressed form are. (i) LPG (Liquefied petroleum gas ) in homes (ii) Oxygen in hospita...

How will you justify that ice, water and steam are the three states of a substance and not different substances ?

When ice is melted, water is produced and when water is heated steam is produced on the other hand, when water is cooled further, ice is produced. Therefore ice, water and steam are the three states of a substanc...

Out of solids, liquids and gases, which one has . (a) Maximum movement of particles (b) Maximum inter particle forces of attraction . (c) Minimum spaces in between constituent particles.

(a) Because of large spaces between the particles of a gas, gases have maximum movement of particles. (b) and (c) In Solids, the spaces between the constituent particles are the minimum and hence the forces of attraction...

Out of dry and wet air which is heavier ?

Since water vapours are heavier than air, therefore, wet air is heavier than dry ai...

How do solids, liquids and gases differ in shape and volume ?

Solids have a definite shape and a fixed volume, liquids have a definite volume but no fixed shape while gases neither have a definite volume nor a definite shap...

Name the physical state of matter which can be easily compressed ?

Gas : Gas is highly compressib...

Define solid, liquid and gas with example ?

Solid : Solids have fireed volume and shape in solids. In solids, particles are closely packed and they have very less spacing between them Examples  : stone, wood, brick etc . Liquid : Liquids have fixed volume but...

Which term is used to describe the mixing of copper sulphate with water in a breaker on its own ?

Diffusion is used to describe the mixing of copper sulphate with water in a beaker on its ow...

What is diffusion ?

The process of mixing of two substances due to Brownian motion of particles is called diffusion. As temperature increases, Brownian motion increases and diffusion becomes fast. Diffusion takes place from higher concentration...

What provides the best evidence about the random motion of particles in matter ?

Diffusion and Brownian motion, provide the best evidence about the random motion of particles in matte...

A diver is able to cut through water in a swimming pool. Which property of matter does this observation show ?

The ability of a diver to cut through water in a swimming pool shows that matter is made up of particle...

List the important properties of matter ?

Properties of matter : - Matter is made up of small particles - These particles are very small in size - These particles are moving constantly - These particles have spaces between them - Particles of matter attract each...

Q.3 A substance has a definite shape as well as definite volume. Which physical state is represented by this statement ?

Solids have a definite shape as well as a definite volum...

What is matter ?

Anything which occupies space and has mass is called matter. In other words, anything which has mass and volume is called matter. For example : chair, table, computer, mouse et...

Name the three common states of matter. Give one example of each ?

Solid (ice), liquid (water), gas (oxyge...

Class 10th Science Solution: Chapter 10 Light-Reflection and refraction

  Question 1:  Which one of the following materials cannot be used to make a lens?  Water  Glass  Plastic  Clay  Answer 1:   (d) A lens allows light to pass through it. Since...