PARALLELOGRAM LAW OF VECTOR ADDITION

	Acccording to the parallelogram law of vector addition:
	"If two vector quantities are represented by two adjacent sides or a parallelogram then the diagonal of parallelogram will be equal to the resultant of these two vectors."
	EXPLANATION
	Consider two vectors . Let t he vectors have the following orientation
	parallelogram of these vectors is :
	According to parallelogram law:
	MAGNITUDE OF RESULTANT VECTOR
	Magintude or resultant vector can be determined by using either sine law or cosine law.

Addition of vectors by Head to Tail method (Graphical Method)

Head to Tail method or graphical method is one of the easiest method used to find the resultant vector of two of more than two vectors.

DETAILS OF METHOD

Consider two vectors A and B acting in the directions as shown below:









In order to get their resultant vector by head to tail method we must follow the following steps:

STEP # 1

Choose a suitable scale for the vectors so that they can be plotted on the paper.

STEP # 2

Draw representative line of vector
Draw representative line of vector such that the tail of coincides with the head of vector .



















STEP # 3
Join 'O' and 'B'.
represents resultant vector of given vectors and i.e.

























STEP # 4

Measure the length of line segment and multiply it with the scale choosen initially to get the magnitude of resultant vector.
STEP # 5

The direction of the resultant vector is directed from the tail of vector to the head of vector .

SCALARS & VECTORS

SCALAR QUANTITIES

Physical quantities which can completely be specified by a number (magnitude)
having an appropriate unit are known as "SCALAR QUANTITIES".

Scalar quantities do not need direction for their description.
Scalar quantities are comparable only when they have the same physical dimensions.
Two or more than two scalar quantities measured in the same system of units are equal if they have the same magnitude and sign.
Scalar quantities are denoted by letters in ordinary type.
Scalar quantities are added, subtracted, multiplied or divided by the simple rules of algebra.

EXAMPLE

Work, energy, electric flux, volume, refractive index, time, speed, electric potential, potential difference, viscosity, density, power, mass, distance, temperature, electric charge etc.

VECTORS QUANTITIES

VECTOR QUANTITIES

Physical quantities having both magnitude and direction
with appropriate unit are known as "VECTOR QUANTITIES".

We can't specify a vector quantity without mention of deirection.
vector quantities are expressed by using bold letters with arrow sign such as:

vector quantities can not be added, subtracted, multiplied or divided by the simple rules of algebra.
vector quantities added, subtracted, multiplied or divided by the rules of trigonometry and geometry.

EXAMPLE

Velocity, electric field intensity, acceleration, force, momentum, torque, displacement, electric current, weight, angular momentum etc.

REPRESENTATION OF VECTORS

On paper vector quantities are represented by a straight line with arrow head pointing the direction of vector or terminal point of vector. A vector quantity is first transformed into a suitable scale and then a line is drawn with the help of the scale choosen in the given direction.

What is the right to education?

Education is both a human right in itself and an indispensable means of realising other human rights. Education is essential for the development of human potential, the enjoyment of the full range of human rights and respect for the rights of others.

It is the primary vehicle by which economically and socially marginalised adults and children can lift themselves out of poverty and obtain the means to participate fully in their communities. Throughout the world, education is seen as one of the best financial investments that a State can make. The importance of education is not just practical. A well-educated, enlightened and active mind, able to wander freely and widely, is one of the joys and rewards of human existence (UN Economic & Social Council, 1999).

The right to education straddles civil and political rights, and economic, social and cultural rights. Core elements of the right to education, as specified in international treaties, include:

• Entitlement to free and compulsory primary education.
• Availability of different forms of secondary education.
• Access to higher education on the basis of capacity and on non-discriminatory terms.
• Availability of accessible educational and vocational information.
• Measures developed by the State to ensure full participation in education.
• Availability of some form of basic education for those who may not have received or completed primary education.
• Protection and improvement of conditions for teachers.
• Respect for the right of parents/legal guardians to choose for their children schools other than those established and funded by the State, and to ensure the religious and moral education of their children conforms with their own convictions.
• Respect for academic freedom and institutional autonomy. This includes the freedom of, and accompanying obligations on, individuals to express opinions about the institution or system in which they work, to fulfil their functions without discrimination or fear of sanction, and to participate in professional or representative academic bodies.

Katarina Toma s evski , United Nation's Special Rapporteur on the right to education, proposes a set of four broad standards (the 4-A scheme) as the basis for assessing the achievement of the right to education. The standards include:

• availability: ensuring free and compulsory education for all children and respect for parental choice of their child's education
• accessibility: eliminating discrimination of access to education as mandated by international law

• acceptability: focusing on the quality of education and its conformity to minimum human rights standards
• adaptability: ensuring that education responds and adapts to the best interest and benefit of the learner in their current and future contexts.

These standards have been adapted for use in the New Zealand context in the form of a Right to Education Framework, He Whare Tāpapa Mātauranga ( Figure 1 ).

Figure 1: The right to education framework: He Whare T āpapa M ātauranga

The right to education involves three key factors: the Government as the regulator, provider and funder of schooling; the student as the bearer of the right to education and the duty to comply with compulsory education requirements; and the child's parents, who are the 'first educators'