> Understanding Measurement

Physics as a master mechanic-hydraulic-fluid mechanics, heavy equipment
measurements require very careful to symptoms
studied can be explained (and predictable) accurately. Actually
measurement is not only absolutely necessary for physics, but also for fields
other sciences, including the application of such knowledge. In other words, no
theory, principles, and laws in natural science that can be
accepted unless accompanied by the results of accurate measurements.

What is a measurement? To find out things
, consider the following descriptions: for example you with your friends
measured the length of the table with hand span. Results
measurements were performed using inch units. For example, if
use your hand span, then the result is the same length of table
with 25 inch arms.

However, if using inch units
your friend's hand so that the same long table with 23 inch arms.
The difference these results suggest that the measurement result depends
the units used. Thus the measurement is defined
as a process of comparing a quantity to other quantities
(A) used as a unit. The unit is comparable in
measurements.

In the above activities, which measure the length of the table that otherwise
with numbers, then the length of the scale. So everything
can be measured and expressed as the number or value is called scale.
For example, table length is 100 centimeters, the length is
scale with 100 as the value and centimeters as units, or
mass table was 20 kilograms, then the mass is the scale with 20
as the value and the kilogram as a unit. Magnitude is `something
can be measured and expressed as the number or value and has units.
The unit is comparable in the measurement.

The measurement is to compare something with something
Another is regarded as a benchmark. So in the measurement there are two
The main factor is the comparison and benchmark (standard). In our junior class 1
have studied the subject of measurement. Here we will only
repeat part of it, to refresh our understanding of
what's contained in the measurement.

READ MORE - > Understanding Measurement

> Quantities and units

The properties of an object or event that we measured, for example
body length, body mass, the length of time running around a
field called the scale, what scale we can measure from a
book?

In a book, we can measure the mass, length, width, and
thick book. How do we express the results of measuring the length of the book?
For example, a book length equal to 25 inches; centimeters called
unit of length scale. The mass of books equal to 1 kilogram, kilograms
called the unit of mass scale. So always follow the scale unit,
never before him.

In our society there is sometimes
units that are not standard or non-standard, such as unit length
selected fathoms or span. The unit is not standard because it does not have
same size for different people. One inch of adult
another with one inch of the children. That is why the span and not depa
used as a standard unit of measurement physics.

Are the conditions that must be possessed of a unit that can be a unit
standard? Some of the main requirements are as follows:

1. Unit value should be fixed, either in hot or cold weather, for people
adults and for children, and to changes
other environments. For example, the span can not be used as a unit
default because different for each person, while
meter applies equally well to adults mapun children. By
therefore, the meter can be used as standard units.

2. Easily recoverable (easy to imitate), so that others who want to
use these units in measurement can
obtain it without much difficulty. Unit mass is kilogram,
easily be recovered by a comparison. Thus,
pounds can be used as standard units. Can we imagine,
how busy if a unit are difficult to make a replica so that the world
there is only one standard unit. Other people who want
measure the amount in question must use only
The standard units to obtain accurate results.

3. The unit must be internationally accepted. It deals with
interests of science and technology. By deterimanya a
unit as international units, the scientists from one country
can easily understand the measurement results from scientists in other countries.

Unit system most widely used around the world, which is valid
in interasional is the SI unit system, short for language
French Systeme International d'Unites. This system was proposed in the General
Conference on weights and Measures of the International Academy of
Science in 1960. In this unit system, there are seven scale
the so-called principal amount.

READ MORE - > Quantities and units

> The amount of principal and derivative

The amount of principal
The amount of principal is the amount that the unit has been defined prior
first. Seven basic quantities in the SI unit system are:
Length (meters)
Mass (kg)
Time (second)
Strong electric current (ampere)
Temperature (kelvin)
Light intensity (candela)
Amount of substance (mole)

Units such as meters, kilograms, and the second is already
defined first. What is the definition of units of
principal amount of these? In the following explanation will be presented definitions
of three basic quantities of length, mass, and time, while unit
Other quantities will be discussed when we discuss the subject
concerned with the amount of vine.

Long
The standard unit for length is the meter in the SI. System of units
based on the meter as a standard measurement system called
metric. At first, the meter is defined as one ten-millionth the distance
between equator and north pole of the earth is measured through the meridian
through the city of Paris. As a standard meter, was made a metal rod
platinum-iridium, which contained both ends of each stroke,
where the distance between two scratches are equal to 1 meter.

In 1960, a standard meter redefined as 1,650,763.73
times the wavelength in vacuum of the color spectrum
orange-red krypton-86 atoms. This is done to re-defining
increase the ease of a standard meter to be made replica, in addition to
to increase accuracy. However, even this definition does not re-
last long, only about 23 years. In 1983, one meter
defined as the distance traveled by light in vacuum during
1/299.792.458 second. With this last definition, complete meters as
standard units meet the requirements specified standard units in front.


Mass
The mass of an object is a number of substances contained in
an object. Mass units in the SI unit system is
kilogram. As a standard for the kilogram, the kilogram standard was made,
which is a metal cylinder made of platinum-iridium, which is now
This is stored in Sevres, near Paris. Initially one kilogram same
with a mass of 1000 cm ³ of pure water at a temperature where the density
maximum, which is 4 º C. But mistakes happen, because it turns out one
kilogram exactly is 1000.028 cm ³ of water.

In everyday conversation, we often confuse the sense mix
mass with weight, but they are different. Weight is the amount of
force experienced by objects due to gravity on the object. For
daily use, is not a confusion of terms
problem, but in physics or an exact science, the definition of mass
and weight should really be distinguished. Has units of mass and weight
different, mass has units of kilograms, while the weight has
Newton unit. The main difference between mass and weight
is that the masses do not depend on the place where the object is located,
while the weight depending on where the object is located. So the weight change
according to the place.

Left
Standard units for time are seconds, which was originally defined
1/86.400 day as the sun. But when scientists found that
solar day is reduced about 0.001 seconds every century, then the second
1/86.400 redefined as solar day in 1900. In
1967, the second was redefined as the time interval from 9192631770
oscillation of the radiation generated by transitions in cesium-133 atom. Tool
measuring time using a cesium atom is cesium atomic clock, which
have a very high accuracy, ie during the 3000 year only
have a second mistake.

The amount of derivatives.
Most of the values which we use in physics and sciences
terapannya (including fluid mechanics and hydraulics, and heavy equipment)
units have a combination of units
principal amount. Such quantities, which determined its unit
based on the principal amount of units, called the scale derivative.
Examples
of the magnitude of this derivative is the area of a square area. Same broad
length times width, where length and width are both
unit length. So vast is the quantity derived from
length scale multiplication with a scale length. Example: Other:
speed (distance divided by time), pressure (force divided by area), the volume of beam
(Length x width x height), discharge (volume divided by time). We know that
speed is the distance (scale length) divided by time. So speed
is a derivative quantity obtained by dividing the amount of
long with the amount of time.

How unit quantities derived from them? It is clear
that the units for the amount of derivatives in accordance with how the
derived quantities were obtained from a combination of basic quantities.

Because the same large scale multiplication of two long, then the unit area
together with the multiplication of two units of length, namely meter x meter = meter
square = m². The unit for speed is the unit of length divided by unit
time, ie meters per second = m / s. It is clear here that that the units
derivative quantities that follow describe the scale derivative. Unit
speed is m / s, mean speed equal to the length (distance) divided
time. The unit for volume is m beam, means the volume is the length
times the length times the length. Density has the units kg / m³, mean mass
type is the mass divided by volume.

READ MORE - > The amount of principal and derivative

> Introduction

Motor vehicles are one of the tools
transportation used by humans to move from
one place to another. Early 19th century's,
vehicle only functioned as a mere means of transportation, it's no wonder
if the manufacturing process has not been touched and aesthetic aspects
comfort. The important thing is the wheels can rotate, so that users can
achieve the goal with a shorter time.

Era of progress and development of automotive technology,
making life increasingly dynamic automotive world. This can be seen from
now motor vehicles not only as a means of transportation, but
developed into a means of creative and achievement, even
vehicles finally become a symbol of a person.
If viewed in terms of shape, the vehicle formerly only shaped
box with a purpose can be used for transporting goods or passengers.

But now, growing very varied forms of vehicles, namely
vehicle with an aerodynamic body, has many accessories and
completeness, and sometimes deliberately designed vehicles that have characteristics
typical of the manufacturer.

The materials used to make cars that time still
the form of wood, then turned into steel that has
good strength, but has a severe weight disadvantage.
Then shifted using eyser plate material, developing
using aluminum body, and present trends in body
fiberglass which has a very light weight.

READ MORE - > Introduction

> History of Vehicle Body

Around the year 1896 - 1910, the vehicle body is made of
timber to the chassis or body. It is still affected
horse-drawn carriage with the body at that time. Wood used to have
thickness of about 10 mm. Connections between components using
nails made of wrought iron. To the roof of the vehicle, there
which uses ordinary cloth, canvas cloth, but some are
using a timber with the aim that the body can be strong.

In 1921, Weymann introduce floor construction
which became the backbone of the other body components, such as wall
vehicles and vehicle seats. The floor is made of a material intentionally
strong, while other components can be made from components
light. Connection with a floor wall using a steel plate
bolted, and to eliminate the gap between the connection usually
used timber. The panels are made of cloth, canvas and exterior
using a skin. However, these materials have a short life.

After the vehicle demand increases, then
required a rapid process of making body and can be produced
mass. The development of metal technology was involved speeding
technology development vehicle body, where the iron can be processed and
formed by using a press machine.

New in 1927 (see figure 1.3) as a whole body
vehicle is made of metal, whereby the vehicle body consisting of
various components has been made of sheet plate formed /
pressed. With the development of metal processing methods are increasingly
increases, the production can also increase vehicle production.

Request a vehicle that continues to increase, causing
there is competition between firms in producing vehicles. Ahliahli
engineering body of each company trying to create the vehicle body
accordance with the needs, ergonomics and comfort and has for
driver and passenger.

The development of the body on the chassis technology from year to
also in progress. For example, wheeled vehicles
initially have a diameter that is not the same, the rear wheels is greater than
on the front wheel, the fingers are made of wood and metal-coated wheels
steel into the wheels that have used both rubber and metal rim
iron or aluminum. Even now no longer tire technology
tire wear in (tubeless tire) that is more secure and easy to use.

The roof of the vehicle (head lining) which was originally only made of
cloth, then shifts made of vinyl or plastic that is more
interesting shape and easy to clean. Assembly process was
relatively easy by using the adhesive (glue).

Passenger comfort in the drive to always
enhanced, for example, seating which has a spring and can be
set position, such as interior door trim, panels, dashboard
made of plastic vinyl or carpet floor that is easy even
cleaned. Steering system that used to use a stick to change
a steering wheel, shift lever to adjust the acceleration also
driver comfort and many other improvements.

Electrical systems also began to be developed. At first light
vehicles using oil, then developed using
acetylene (carbide) and now use a battery as a source of
electricity. Functions that used to light only as a means of lighting in
night, when this light is also used as a cue and ramburambu
in an effort to improve safety in driving.
The lights also be of interest for vehicle accessories
enhance the look of the vehicle.

The development of vehicle body, also plays an important role
in terms of vehicle capabilities. The first time the steam engine vehicles
Cugnot created, can only walk about 5 km / h, but when
These vehicles can run at speeds above 100 km / h
but still comfortable, safe and not noisy.

Most people probably only think that the speed depends on the engine, will
but this time people began to realize that the speed of the vehicle also
influenced by the stability of the vehicle as well as shape and surface of the body
vehicle. As in racing, aerodynamics of a vehicle
it is essential to achieve the speed and stability of the vehicle,
this is the case with ordinary vehicles, now becomes one body
one very important and always made the development.

READ MORE - > History of Vehicle Body

> Body Construction Vehicles

Car parts are divided into 2 major groups, namely the body and
chassis. Part of the vehicle body is formed in such a
way, (in general) made of metal plate (steel plate) which
thickness between 0.6 mm - 0.9 mm as a passenger or goods.

Chassis is part of the vehicle that serves as
sustaining the body and consists of the frame (frame), engine (engine), power train
(Energy transfer), wheels (the wheels), steering system (steering system),
suspension system (suspension system), brake system (brake system) and
Other completeness.

Based on the attachment of the body on frame construction, the
there are 2 types of vehicle body construction, ie composite construction
(Alone) and construction monocoq (attached).

Framework is attached to his place all the components
vehicle including the body. Framework must be strong, lightweight, sturdy and resistant
to vibration, or shock received from the condition of the road. Facebook
strong then there is a box truss construction, the shape of U or pipe, which
generally consists of two rods that elongate and connected
with a transverse section. In the early development of body technology
and the vehicle frame, body and frame are made separately
(Composite body) but lately the body and frame are made together
(Monocoque body, also called the integral body), especially in
sedan vehicle.

Separate Construction (Composite)
It is a type vehicle body construction where the body and chassis
separately. Linkage / connection between body and frame using
bolts and nuts. To improve comfort during use, then
between body and frame mounted rubber as a means of dampening vibration.

Construction framework of a separate body and this makes it easy
in replacement of vehicle body parts were damaged,
body especially the lower-or-break order. This construction
usually used on the old type of sedan vehicles, vehicle
passenger and freight cars. (Eg trucks, buses, pick-ups and
etc.).

Converge construction (monocoque)
It is a type vehicle body construction where the body and frame
composed into a single unit. This construction uses the principle of skin
eggs, which is a unified whole so that all load
divided evenly on all parts of the skin. Linkage between body and
order to use the weld.

Because the body and frame together, then the shape can become more
low compared with the composite type so that the point of gravity weight
lower will cause the vehicle more stable. This construction
used on the sedan, even a few vehicles MPV (Multi Purpose
Vehicle) began implementing monocoq body construction.

Frame Types
Based on the shape, order vehicles can be divided into several
types, namely: (a) order form H, (b) frame the perimeter, (c) frame
form X, (d) framework forms the backbone (backbone), and skeletal
form the floor (platform frame).

Order form H.
Its construction is very simple, easy to make, widely used for
vehicle bus, truck.

Perimeter Frame.
Framework of the perimeter is a revised form of H, the body attached
on the edge of the frame so that the position of the floor can be lowered. Reduction
floor of the vehicle will lower the center of the vehicle weight and height
reduced vehicle so that steering a steady, passenger space
become more freely, widely used for the sedan.

Order form X.
Beam frame construction consists of two rod-shaped main frame
longitudinal beams together in the middle. Place of engagement with
body and the doors can be made low enough for easy in and out
vehicles, robust against rotation, used to the old type sedan.

Order forms Spine (Back Bone).
Construction framework of a single model framework, the middle
bear the burden (back) and arms that stand out as the holder
body. This kind of frame construction also allows the center weight
vehicle is made lower. Construction framework of this model often
used for passenger cars and trucks.

Floor Model Frame (Frame Platform).
Body and frame welded into one, so it is a form
integrated, allowing the interior space is made large. Another advantage
the use of frame construction this model is resilient
good enough against bending and torsion.

READ MORE - > Body Construction Vehicles