When one surface is moving over another surface, a force comes into play and opposes their relative motion. This force is called friction or force of friction. Friction always opposes motion because it acts in opposite direction to motion. Force of friction arises due to contact between two surfaces. If there is no contact between two surfaces there would be no friction.

• We know that all living organisms like plants and animals need food, oxygen and water so that they can survive.

• These elements need to be delivered to their body parts so that they can function properly.

• Hence, all living organisms need a transport system in their bodies.

• The circulatory system is a transport system of the human body which consists of a network that supplies food, water, oxygen and other substances throughout the body.

18(2x-3y)-6(3y-2x)

= 36x - 54y - 18y + 12x

= 36x + 12x - 54y - 18y

= 48 x - (54 + 18)y

= 48x -  72 y

The Scheduled Castes and Tribes (Prevention of Atrocities) Act, 1989 an Act of the Parliament of India enacted to prevent atrocities against scheduled castes and scheduled tribes.
Article 17 of Indian Constitution seeks to abolish 'untouchability' and to forbid all such practices. It is basically a "statement of principle" that needs to be made operational with the ostensible objective to remove humiliation and multifaceted harassments meted to the Dalits and to ensure their fundamental and socio-economic, political, and cultural rights.
The normal provisions of the existing laws like, the Protection of Civil Rights Act 1955 and Indian Penal Code have been found inadequate to check these atrocities<a href="http://en.wikipedia.org/wiki/Scheduled_Caste_and_Scheduled_Tribe_%28Prevention_of_Atrocities%29_Act,_1989#cite_note-1"> </a>continuing the gross indignities and offences against Scheduled Castes and Tribes. Recognizing these, the Parliament passed ‘Scheduled Caste and Scheduled Tribe (Prevention of Atrocities) Act’.
The purpose of the Act was to help the social inclusion of Dalits  into Indian society, but the Act has failed to live up to its expectations admitted by the Union Minister for Home Affairs in parliament on 30 August 2010.

Articles 14,15,28,29 and 30 of the constitution have protected the intrests of the minority communities in India. ARTICLE 14 provides equality before law and equal protection which provide protection against discrimination irrespective of religion or caste.
ARTICLE 28 safeguard the minority from enforceable religious teachings (such as dress code for specific prayers and all) in all government funded educational institutions.
article 29 provide protection of language , script, culture and conserve the same.
The constitution has declared India to be a secular country in which people of each and every religion has the right to profess, practice and propagate their own religion.

The tiny atomic nucleus is the centre of an atom constituting positively charged particles known as  “protons”.

Both the protons and neutrons reside in the nucleus.

Let a is the edges of cube.

and Total surface area of cube = 864
6a sq. = 864
a sq. = 864 / 6
a = 144 under root
a = 12 cm

First ten natural no. are 1 , 2, 3, 4, 5, 6, 7, 8, 9,10
Mean = Sum/Number
mean = 1+2+3+4+5+6+7+8+9+10/10
= 55/10
= 5.5
The average of first ten natural numbers is 5.5.

Sound is produced when something vibrates. The vibrating body causes the medium (water, air, etc.) around it to vibrate. Vibrations in the air are called travelling longitudinal waves, which we can hear. Sound waves consist of areas of high and low pressure called compressions and rarefactions, respectively.

The container of soda acid fire extinguisher holds a sodium bicarbonate solution.

The screw-on cap contains a plunger mechanism which is covered by a safety guard. Below the plunger is a glass phial containing sulphuric acid.

When the plunger is struck, the glass phial is broken and the acid and sodium bicarbonate mix together (observe the diagram given below).

The resulting chemical reaction produces carbon dioxide gas which pressurises the space above the liquid forcing it out through the internal pipe to the nozzle.

When two plane mirrors are kept inclined at an angle, they can form multiple images of an object because the image of the object formed in one plane mirror acts as object for the other plane mirror.

The two plane mirrors arranged at right angles to each other form three images of an object placed between them. As the angle between the two plane mirrors decreases, the number of images formed increases. If an object is placed between two parallel plane mirrors facing each other, then an infinite number of images should be formed.

Their marginalisation can be because they speak a different language, follow different customs or belong to a different religious group from the majority community. They may also feel marginalised because they are poor, considered to be of ‘low’ social status and viewed as being less human than others.

Sometimes, marginalised groups are viewed with hostility and fear. This sense of difference and exclusion leads to communities not having access to resources and opportunities and in their inability to assert their rights. They experience a sense of disadvantage and powerlessness vis-a-vis more powerful and dominant sections of society who own land, are wealthy, better educated and politically powerful.

The two plane mirrors arranged at right angles to each other form three images of an object placed between them. As the angle between the two plane mirrors decreases, the number of images formed increases. If an object is placed between two parallel plane mirrors facing each other, then an infinite number of images should be formed.