History and Evolution
of Automobiles
Automobile:
Source:AxleAddict
Automobile is a wheeled motor
vehicle used for transporting goods or passengers, which also carries its own
engine or motor.
Source:Giffer.com
AUTOMOBILE=AUTO+MOBILE=SELF+MOVABLE = SELFMOVABLE VEHICLES
Automobiles are designed to run primarily on roads, to have seating
for one to eight people, to typically have four wheels, and to be constructed
principally for the transport of people
and goods.
Invention
of Wheel
The wheel is considered as one of the most important
mechanical inventions of all times. The wheel has been
used by man since the beginning of civilization. Most
primitive technologies since the invention of the wheel
have been based on its principles.
Various ages of Wheel Invention
4500 BC: Invention of the potter’s wheel,
Chalcolithic (Ubaid period)
4500–3300 BC: Chalcolithic, earliest wheeled vehicles,
domestication of the horse
3300–2200 BC: Early Bronze Age
2200–1550 BC: Middle Bronze Age, invention of the
spoked wheel and the chariot
Since the Industrial Revolution, the wheel has been
a basic element of nearly every machine constructed by
mankind. While the exact time and place of the invention
of the wheel has been disputed, its beginnings can be
seen across ancient civilizations.
History tells us that wheel was most likely invented
in Mesopotamia (modern day Iraq) around 3500 BC.
This means that the wheel is about 5500
years old.
The first use of the wheel for transportation was in
Mesopotamian chariots in 3200 BC. There are many
references to wheeled chariots in Indian mythology
also, dating to around 3000 BC. It is interesting to
note that wheels may have been used in industrial
or manufacturing applications before they were
used on vehicles. Egyptians started using wheel with
spokes, first in chariots around 2000 BC and use
of wheels is believed to have started in Europe by
1400 BC
Wheel and Its Structure
It is hard to imagine any mechanized system that would
be possible without a wheel or a idea of a symmetrical
component moving in a circular motion about an axis.
From tiny watch gears to automobiles, jet engines and
computer disk drives, the principle is the same.
Early wheels were simple wooden disks with a hole
for the axle. Due to the structure of wood, a horizontal
slice of a tree trunk is not suitable, as it does not have
the structural strength to support weight without
collapsing; rounded pieces of longitudinal boards
are required.
The oldest known example of a wooden wheel and
its axle was found in 2003 in the Ljubljana Marshes
some 20 km south of Ljubljana, the capital of Slovenia.
According to the radiocarbon dating, it is between 5100
and 5350 years old. It has a diameter of 72 centimetres
(28”) and is made of ash wood, whereas its axle is made
of oak.
The invention of the wheel has also
been important for application in
the water wheel, the cogwheel, the
spinning wheel and the astrolabe or
torquetum. More modern descendants
of the wheel include the propeller, the
jet engine, the flywheel (gyroscope) and
the turbine. Therefore, we see that a
wheel is a circular component that can rotate on its centre. Wheels,
in conjunction with axles, allow moving
heavy objects with ease. The wheel is the
main component of the wheel and axle
assembly. Wheel and axle were used in
the first carriages.
The wheel is a device that enables efficient movement
of an object across a surface where there is a force
pressing the object to the surface. Common examples
are a cart pulled by a horse and the rollers on an aircraft
flap mechanism.
The low resistance to motion (compared to dragging)
is explained as follows.
• The normal force at the sliding interface is the
same.
• The sliding distance is reduced for a given distance
of travel.
• The coefficient of friction at the interface is
usually lower.
The classic spoked wheel with hub and iron rim
was in use from about 500 ACE (Iron Age Europe) until
the twentieth century AD. We can see the importance
of wheel in various places and its role in our day‑to day life. Our national flag also has a circle signifying
a wheel with spokes.
Invention of wheel notes
A. Fill in the blanks
1. _Wheel ,
is considered as one of the most important mechanical inventions of all time.
2. Wheel was invented in _Mesopotamia__ around 3500 BC which is _5,500_ years back
3. A wheel is a _circular_
component that can rotate on its centre.
4. Wheel is a _device__
that enables efficient movement of an object___
across a surface where there is a force pressing the object to the surface.
5. The coefficient of friction at the interface of wheel is
usually _lower_.
B. Answer
the following
1. What is wheel?
Wheel is a circular component that can rotate
on its centre
2. Components of a wheel
The
wheel is the main component of the wheel
and axle assembly.
3. Materials of wheel
Wood,
stone , metals , alloy’s etc
4. Design of the wheel
·
The normal force at the sliding interface is the
same.
·
The sliding distance is reduced for a given
distance of travel.
·
The coefficient of friction at the interface is
usually lower.
C. List the items where wheel is used as a part of machinery.(Activity by students)
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