CHAPTER - 5

                  INDUSTRIES

• Secondary activities are those activities which change raw materials into products of more value of people. 

• Industry refers to an economic activity that is concerned with production of goods, 

extraction of minerals or the provision of services. 

• Raw Material: Industries under this are of agro-based, mineral-based marine-based and 

forest-based.

• size of Industries: 

(i) Size refers to the amount of capital invested, number of people employed and the 

volume of production. 

(ii) Industries based on size are classified into small scale and large scale industries. 

• Small Scale Industries: 

(i) Small scale industries manufacture products by hand and include cottage and 

household industry. These industries use lesser amount of capital and technology. 

(ii) For example, Basket-weaving, pottery and other handicraft industries. 

• Large Scale Industries: 

(i) Large scale industries produce large volumes of products. The investment of capital is 

higher and technology is superior. 

(ii) For example, production of automobiles and heavy machinery. 

• Ownership: On the basis of ownership, industries can be classified into the following 

sectors: (a) Private sector, (b) Public sector or state owned, (c) Joint sector, (d) Cooperative 

sector.

• Private Sector Industries: 

(i) Private sector industries are owned and operated by individuals or a group of 

individuals. For example, Bharat Heavy Electrical Ltd., Indian Oil Cooperation. 

(ii) Public sector industries are owned and operated by the government. For example, 

Hindustan Aeronautics Limited and Steel Authority of India Limited. 

• Joint Sector Industries: Joint sector industries are owned and operated by the state and 

individuals or a group of individuals. For example: Maruti Udyog Limited.

• Cooperative Sector Industies: These industries are owned and operated by the producers 

or suppliers of raw materials, workers or both. For example: Anand Milk Union Limited and 

Sudha Dairy.

• Factors Affecting Location of Industries: 

(i) The availability of raw material, land, water, labour, power, capital, transport and 

market are the factors and market are the factor affecting the location of industries. 

(ii) Industrialization leads to development and growth of towns and cities. 

• Industrial System: 

(i) An industrial system consists of inputs, processes and outputs. 

(ii) Raw materials, labour and costs of land, transport, power and other infrastructure are 

the inputs. 

(iii) The processes include a wide range of activities that convert the raw materials into 

finished products. 

(iv) The result or the outputs are the end of product and income earned from it.

RULES AND LAW : THE CONSTITUTION

For the functioning of any democratic country, rules and laws are always necessary. These rules and laws make life easier and functioning of democracy effective as well as a smooth.

If we do not follow these rules, our safety and security will be threatened. In the same way, certain rules and regulations are a must for the working of the state or a country. The set of rules and regulations which helps in the smooth functioning of the state is termed as constitution.

ROLE OF THE CONSTITUTION
A constitution is a set of return rules and laws according to which a state is governed.  The constitution lays down guidelines and principles on the basis of which the governance of that country is conducted with a view to maintain law and order.

TYPES OF CONSTITUTION
The constitution is of two types -
1. Written constitution
2. Unwritten constitution.
    Our country has a written constitution which came into force on 26th January, 1950.
The Constitution is very important for a state due to the following reasons :
• The government of a country is formed and functions on the guidelines laid down in the Constitution.
• It helps us to understand the political system of a country.
• It delimits the scope and activities of various organs of the government.
• It ensures that the citizens of a country enjoy they are Fundamental Rights.

Note : One of the famous scholar 'Jallinek' describes the importance of the Constitution as -
    " A state without constitution would not be a state but a regime of anarchy."

WHAT ARE LAWS? WHY DO WE NEED LAWS?
The laws is defined as a set of rules and regulations according to which country is governed and are widely recognised by society. The U.S President, Woodrow Wilson, described the law as " the portion of the establishment thought and habit which has gained distinct and formal recognition in the shape of uniform rules backed by authority and power of the government."
Laws have their own important in the society. We need laws -
• as they regulate the civil life of the society.
• for good governance.
• to maintain law and order.
• to curb the society evils prevailing in the society.

Several laws has been passed and implemented to safeguard the people.
• Dowry prohibition Act of 1961: The practice of dowry is prevalent in the society since time immemorial. Dowry is a gift or a some of money given to a daughter by her parents on the eve of her marriage. Initially, it was not compulsory, what's it became a traditional. Unfortunately, it has become a major problem. The ill consequences of dowry are beyond imagination. In urban, suburban and rural areas, a newly married women is harassed and tortured by the husband and his family members for not bringing sufficient or the demanded dowry. Sometimes, these newly married women sre killed or even forced to commit suicide to escape the ill-treatment meted out to them by their in-laws.

To curb this social evil, the Dowry Prohibition
Act was implemented in 1961. According to this Act, demanding and giving of dowry offence. Anyone found guilty of demanding or giving dowry will be fined or imprisoned for a period of not less than five years.
• Sati Prevention Act : This evil is practised in India since the medieval period. It is the practice of burning of widow on the pyre of her husband. Many social reformers like Raja RamMohan Roy and Dayanand
Saraswati did their best to their social evil.
In 1987, in Deorala village of Rajasthan, Roop Kunwar's tryst with the tradition,led to a widespread reaction throughout the country.  The government soon passed a law under Sati Prevention Act, 1987 to punish the entire village who just stood and watched a lady being prey to the evil practice of Sati.

                          PRESSURE

Pressure :- The effect of force over a unit area is called pressure.

-Thrust or normal force :- The force that acts normally  (perpendicular) over a surface is called trust or normal force.

* S.I. unit of pressure is Pascal (Pa).

* Pressure = Force/ Area.

• Pressure is directly proportional to the force.

- Pressure (increase) force will also (increase).

- Pressure (decrease) force will also (decrease).

• Pressure inversely proportional to the area.

- Area (increase) pressure will (decrease).

- Area (decrease) pressure will (increase).

1Pa = 1N/1m2 = 1N/m2= 1Nm2

When 1N of force acts perpendicular to the surface of unit area than the pressure is said to be 1 pascal.

- Another unit of pressure is bar, atm, etc.

• 1bar = (10)5 pascal.

RELATION BETWEEN AREA AND PRESSURE:-

SbRELATIONSHIP BETWEEN AREA A

• Area is less than pressure is greater between paper and pencil.

So, the tip of pencil easily pierce the paper.

• The area is more than the pressure is lesser between paper and the end of pencil.

So, the ends of pencil cannot pierce easily to the paper.

• It is more comfortable to wear broad heels while walking on soft surface.

• Elephants and bears have broad feet to help them walk on soft surfaces without falling.

• The width of straps of bags and suitcases is increased to reduce pressure while carrying them.

RELATION BETWEEN FORCE AND PRESSURE :-

• For the same area, when the force applied increases, the pressure increases.

• When the forces decreases, the pressure decreases.

PRESSURE EXERTED BY LIQUIDS :-

• The pressure exerted by liquid depends upon the depth of the water column.

• They exert pressure not only at the base of the container but also on its sides.

Liquid pressure varies with depth:-

• Water from the lowest hole comes out with the greatest force and falls at the maximum distance.

• Water from the topmost hole comes out with the least force and falls at the minimum distance.

* An instrument used to measure liquid pressure is called pressure gauge. The simplest form of a pressure guage is a manometer.

ATMOSPHERIC PRESSURE 

- The pressure exerted by the weight of the air on an object is called atmospheric pressure.

• ALTITUDE :-  The height of a place above the sea level is known as altitude.

* The scientific instrument used in meteorology to measure atmospher pressure is Barometer.

Atmospheric pressure decreases with altitude 

The height and weight of the air column decreases as we go up. Therefore, the atmospheric pressure also reduces as we go to higher places. Hence, the atmospheric pressure at a place depends on its altitude.

FORCE OF ATMOSPHERIC PRESSURE

• The pressure exerted by atmosphere is very large. This was demonstrated by a German physicist and engineer,  Otto von Guericke. He took two semicircular copper bowls and fitted them together to form a sphere. Then he sucked all the air from the sphere using a suction pump to create a vaccum inside the sphere. The two bowls were now held together only due to the atmospheric pressure. Then he tried to separate the two bowls by getting them pulled apart by a team of eight horses on each side. The bowls remained held tightly together due to the atmospheric pressure and did not separate. This proved the enormous force of atmospheric pressure.

       PHYSICAL AND CHEMICAL

                       CHANGES

                     FRICTION

Friction :- It is the force that opposes the motion of an object.

Factors affecting friction : -
(i) it is caused by the irregularities on the two surfaces in contact.
(ii) When the surfaces on any two objects are in contact, these tiny hills and grooves  entangle or interlock with each other opposite motion. When we attempt to move any one object, we have to apply force to overcome interlocking.

* Friction increases as the mass increases.

* Friction produce heat.

The factor of friction depends on the :-
• Nature of surfaces in contact.
• Mass of objects in contact.

TYPES OF FRICTION 

(i) Static friction :- Static friction is the frictional force that exists between two bodies as long as they are relatively at rest,  even though an external force is acting upon them.

(ii) Sliding friction :- The force of friction acting between two bodies when they slide  on another with a uniform speed is called sliding friction.

(iii) Rolling friction :- The force of friction that exists between two surfaces when a body rolls over the other body is cold rolling friction.

FLUID FRICTION
• The frictional force exerted by fluids is called drag.
• This drag depends upon the shape, material and the speed of the object.
• Fluids friction is minimum for objects that are narrow in front and broad at the back. This is called a streamlined shape.
Example - Boats and Ships have streamlined bodies to help them move through water easily.
* The substances which reduce friction is call lubricants.

ADVANTAGES OF FRICTION
Friction plays an important role in our daily life. Some examples to prove this are given below : -
• Friction between our feet or foot wear and the ground helps us to work without sleeping. That is why it is difficult to walk on Ice or on a smooth polished floor.
• The friction between the treaded tires and the rough surface of the road enables vehicles to move safely on the road. That is why we observe more incidents of vehicles skidding on greasy or wet roads on rainy days.
• Friction between the brake shoe and the wheel slows down or stops a  moving vehicle.
• We are able to light a matchstick, sew clothes, tie a knot or fix a nail on the wall because of friction.
• Friction between a pencil or a pen and paper helps us to write. That is why we find it difficult to write on smooth surfaces like plastic, glass, etc. It is friction that allows your teacher to write on the blackboard.

DISADVANTAGES OF FICTION
The advantages of friction are numerous. But it has some disadvantages too:-
• Friction wears out the rubbing surfaces like screws and ball bearing of machines or soles of shoes.
• The objects in contact require more force to overcome friction between their rubbing surfaces. This results in wastage of energy.
• You already knowo that friction generates heat. This heat raises the temperature of a machine, sometimes causing damage to its parts. Hence, proper arrangements have to be made to keep the machine cool. For example, insulation of windings of machines like mixer grinders, hair dryers, etc. may get spoiled due to friction and the motor may burn.

INCREASING FRICTION
We use different techniques to increse friction : -
• Roughen the surfaces
• Dry the surfaces
• Use brake pads

REDUCING FRICTION 

In some situations however, friction is undesirable and we minimize it by using different methods : -
• Polishing the surface
• Lubricating the surfaces
• Using wheels and ball bearing
•Streamlining

                    What is Force?

Force :- Push or pull that affects an object in some way is called a force.
• Force is measurable quantity.
• SI unit of the magnitude of force is Newton (N).
• Force has both magnitude and direction.
[Vector quantity].

EFFECT OF FORCE :-
(i) Force can make a stationary object move.
(ii)  Force can stop a moving object.
(iii) Force can change the speed of a moving object.
(iv) Force can change the direction of moving object.
(v) Force can change the shape of an object.

THERE ARE TWO TYPES OF FORCE :-
(1) Contact force.
(2) Non-contact force.

1. Contact force - Force which require physical contact is known as contact force.
*There are three types of contact force :-
(i) Muscular force
(ii) Mechanical force
(iii) Frictional force

Muscular force - A force that requires that action of Muscles of our body is called muscular force.

Mechanical force - The force generate by a machine (for example the engine of a car) is called mechanical force.

Frictional force - [oppose relative motion]
Force that opposes motion whom two surfaces in contact move or tend to move with respect to each other is called Frictional force.
-  The direction of this force is opposite to the direction of motion.
- It has internal force
- It always generate in pair.

2. Non-contact force - Force that arise due to interaction between objects that are not in physical contact are called Non-contact force.
- Also known as distance force.
- Non-contact forces act From a distance.

* There are three types of Non-contact force:-
(i) Gravitational force
(ii) Magnetic force
(iii) Electrostatic force

Gravitational force - Every object is pulling every other object towards itself. This force of attraction called gravitational force.
- Force acts between two bodies.
- Always attractive.
- Internal force.
- Central force.

• Gravitational force = Gm1m2/r2

Magnetic force - Magnetic force is a force that attracts certain metal objects (like iron and iron fillings) towards a magnet is called magnetic force.
- Magnetic force can be both attractive and repulsive.
• Like pole repel each other.
• Unlike pole attract each other.

Electrostatic force - Force between the  two charged bodies exert a force on other changed or uncharged bodies is called electrostatic force.
- This force deos not require physical contact between the two bodies.
- Non-contact force.
- Central force.
- Electrostatic force could be both attractive and repulsive.

• Two charged bodies repel ech other.
• Two uncharged bodies attract each other.

There are two types of charge:-
(i) Positive charge (+).
(ii) Negative charge ( - ).

BALANCE FORCE :-
Two or more forces acting on an object are said to be balanced forces, if the net affect produced by all the object is zero (0).
- The balanced forces do not change the state of the body.

UNBALANCED FORCE :-
If the net affect produced by two or more forces on an object is not zero, then the forces are said to be unbalanced forces.
- The unbalanced forces change the state of the body.

                     FIRE AND ICE

 INTRODUCTION - 

This short poem outlines The familiar question about the fate of the world, wondering if it is more likely to be destroyed by fire or ice. People are on both sides of the debate.

 SUMMARY-

'Fire and ice' is a short poem by Robert Frost. In this poem, the poet refers to two predictions of how the world will end. Some say it will end in fire while others say it will end in ice.  According to the poet 'fire' stands for desire, greed, avarice or lust. The more you try to satisfy them, the more they grow. There is no end to it. They spread rapidly like fire and engulf your whole life. One become selfish and sometimes cruel also. On the other hand, 'ice' according to the poet, stands for hatred, cloudness and rigidity. One becomes insensitive and indifferent towards the feelings of others. The poet says the both fire and ice are growing with such a rapid speed that the world would soon Parish either way, in fire or in ice.

Explanation of the poem 

1.  Some say the world will end in fire,

     Some say in ice.

     From what I have tasted of desire

     I hold with those who favour fire.

   Explanation :  The poet says that there are two notions in the society about the destruction of the world. The first of these theories states that fire will cause the disaster to happen. He equates fire with human passion and desire. The poet frankly confesses that  he agrees with those people who believe that the world will be burnt by fire.

2.  But if it had to Perish twice,

      I think I know enough of hate

      To say that for destruction ice

      Is also great

      And would suffice.

    Explanation - In these lines, the poet stops      discussing the first theory and goes on to talk about the second theory - the theory about the destruction of earth by ice. He does not disagree with the first theory about fire. He simply considers what might happen if the earth were to be destroyed a second time. He is sure that the second time ice will be enough to destroy the earth as nearly and effectively as the fire. He then compares ice with hatred.