Thursday, January 7, 2010

Trichomonas Wont Go Away

VECTOR SYSTEM inequalities

A vector is a physical quantity characterizable by a module and a direction or orientation, which can be represented in polar coordinates by adding the orthogonal vector components parallel to the coordinate axes. Alternatively, a more formal and abstract, a vector is a physical quantity, which set a base, represented by a sequence of numbers or independent components such that their values \u200b\u200bare systematically relatable when measured by different observers.
Example
The distance between two cars
start from the same site can not be determined solely by its speed, this is, the modules of their speeds. If they are 30 and 40 km / h, to spend an hour, the distance between them may be, among other possibilities:
of 10 km, if the two cars are moving in the same direction.
From 70 km, if they move towards contraria.De 50 km, if they move in perpendicular directions.
Thus, the distance between the two cars depends not only on the speed of the cars (which marks the speedometer). It is necessary to define the rate vector character, ie the numerical data link address (or module).


scalars AND VECTORS


face those physical quantities such as mass, pressure, volume, energy
ed, temperature, etc., which are completely defined by a number and the units used in measurement, there are others, such as displacement, velocity, acceleration, force, the electric field, etc., which are not
c omplete
giving a numerical data set, but are associated with an address. The latter are called vector quantities as opposed to the first ones are called scalars.


The scalars are represented by the general m
simplest thematized, for a number. The vector quantities are represented by a mathematical entity called a vector. In a space Euclidean, not more than three dimensions, a vector is represented by a directed line segment. Thus, a vector is characterized by the following elements: its length, or module, always positive by definition, and its direction determined by the angle between the vector with the coordinate axes. Thus we can state:
A vector is a physical quantity that has magnitude and direction.
is represented as a directed line segment, with an address, drawn in a similar way "arrow." Its length is the mod
Ulo
vector and "Arrowhead" indicates its direction, which is measured in polar coordinates.


NOTATION

The vector quantities are represented in the printed texts of letters in bold to distinguish them from scalar quantities that are represented in italics. In the manuscripts, the vector magnitudes are represented by placing an arrow on the letter that identifies your module (Which is a scalar). Examples:
... represent, respectively, the vector magnitudes of modules A, a, ω, ... The module is also a vector quantity is enclosed in slashes for the vector notation: ... In the manuscripts
write: ... for vectors and ... or ... for modules.

Where appropriate, we represent the vector magnitude reference to the origin and the end of the line segment that represents geometrically so, denote the vectors represented in Figure 2 on the way ... This notation is very useful for vectors displacement.
addition to these conventions or vestors unit vectors, whose magnitude is unity, are represented with a circumflex over frequently.


TYPES OF VECTORS

According to the criteria used to determine equality or two equipotent vectors, we can distinguish different types of them:

Vectors free: they are not applied at any point in particular.Vectores sliding: its point of application can slide along the line of action. Vector
fixed or linked, are applied in a particular point.

We also refer to:

unit vectors: unit vectors module. Concurrent Vector
: its lines of action converge at a point proper or improper (parallel). Vector
opposite: vectors of equal magnitude but opposite direction. Collinear vectors
:
sees
ctor that company
rten same line of action.
coplanar vectors: the vectors which are coplanar lines of action (located in the same plane)


COMPONENTS OF A VECTOR


A vector space can be expressed as a linear combination of three unit vectors perpendicular or vestors to provide a basis vector.
In Cartesian coordinates, the are represented by unit vectors i, j, k, parallel to the axes of coordinates x, y, z positive. The components of the vector into a default base vector can be written in parentheses and separated by commas:
or expressed as a combination of unit vectors defined in the base vector. Thus, in a Cartesian coordinate system will be otherwise.

These representations are equivalent to each other, and the values \u200b\u200bx, y, z are the vector components, unless otherwise indicated, are real numbers.


OPERATIONS WITH VECTORS


Vector Addition:

To add two vectors and vector free vector are chosen as representatives of two vectors such that the tail end of a match with the source end of another vector.


parallelogram method
:

is to have two vectors graphically so that the origins of both agree on one point, completing a parallelogram by drawing lines parallel to each of the vectors in the extr
emo the other (see graphic at right). The result of the sum is the diagonal of the parallelogram of the common origin of both vectors.


triangle method:

is to have a vector graphic after another, ie the origin of a vector is carried over the end of another. Here are links the origin of the first vector with the end of the second.


analytical method. Sum and difference vectors:

Given two free vectors,

  \mathbf{a} = (a_x \mathbf{i} + a_y \mathbf{j} + a_z \mathbf{k})
  \mathbf{b} = (b_x \mathbf{i} + b_y \mathbf{j} + b_z \mathbf{k})

The result of the sum or the difference is expressed how
 \mathbf{a} \pm \mathbf{b} = (a_x \mathbf{i} +a_y \mathbf{j} +a_z \mathbf{k}) \pm (b_x \mathbf{i} +b_y \mathbf{j} +b_z \mathbf{k})

and ordering the components,

  \mathbf{a} \pm \mathbf{b} =  (a_x + b_x) \mathbf{i} + (a_y + b_y) \mathbf{j} + (a_z + b_z)\mathbf{k}
Known
modules given two vectors a and b and the angle θ formed between itself, the module is:

 |\mathbf{a} \pm \mathbf{b}| = \sqrt{a^2 + b^2 + 2ab \cos \theta}
The derivation of this expression can be found on deduction of the sum module.
product of a vector by a scalar


PRODUCT OF A VECTOR BY A SCALAR

The product of a vector by a scalar is another vector whose magnitude is the scalar product of the magnitude of the vector, whose direction is equal to the vector, or against it if the scale is negative.
Based on the graphical representation of the vector, on the same line so many times we address the vector form as check scaling.

Based on a scale, "N" and a vector "A", the product of "N" to "A" is represented and is done by multiplying each of the components of the vector by the scalar that is, given the vector

  \mathbf{a} = a_x \mathbf{i} + a_y \mathbf{j} + a_z \mathbf{k}

your product is the scalar
  n \, \mathbf{a} = na_x \mathbf{i} + na_y \mathbf{j} + na_z \mathbf{k}

that is, multiplied by "N" each of the components vector.




DERIVATIVE OF A VECTOR

Given an array is a function of independent variable

  \mathbf{a}(t)=  a_x(t) \mathbf{i} +a_y(t) \mathbf{j} +a_z(t) \mathbf{k}

estimate the derivative of the vector with respect to variable t, by calculating the derivative of each of its scalar components as if it were:

  \frac{d}{dt}\mathbf{a}(t)=  \frac{d}{dt}a_x(t) \mathbf{i} +  \frac{d}{dt}a_y(t) \mathbf{j} +  \frac{d}{dt}a_z(t) \mathbf{k}

taking note that the unit vectors are constant in magnitude and direction.

An example of derivation of a vector, based on a vector function:

  \mathbf{r}(t) =  \sin(t) \mathbf{i} + \cos(t) \mathbf{j} + 5t \mathbf{k}

This function represents a helical curve around the z axis, of unit radius, as illustrated in Fig. We can imagine that this curve is the trajectory of a particle and the function represents the position vector function of time t. Differentiating we have:

Performing the derivative:

The derivative of the position vector with respect to time is speed, so this second function determines the particle velocity vector versus time, we can write:

This velocity vector is a vector tangent to the trajectory at the point occupied by the particle at every moment. If derivásemos again would get the acceleration vector.

angle between two vectors

The angle determined by the directions of two vectors A and B is given by:

  \cos \theta = \frac {\mathbf a \cdot \mathbf b}{|\mathbf{a}| \, |\mathbf{b}|}








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