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  Thermodynamics and Heat Transfer   THERMO DYNAMICS In the subject of thermodynamics, the inter-relationship among heat, work and system properties are studied. It is also called as the conceptual science of entropy and energy. Some Thermodynamical Terms in brief (i) Thermodynamic system: A thermodynamical system is an assembly of large number of particles which can be described by thermodynamic variables like pressure (P), volume(V), temperature(7). (ii) Surroundings: Everything outside the system which can have a direct effect on the system is called surroundings. The gas cylinder in the kitchen is the thermodynamic system and the relevant part of the kitchen is the surroundings. (iii) An adiabatic wall: The wall which prevent the passage of matter and energy. (iv) Diathermic wall: It prevent the passage of matter but allow the passage of energy. An aluminium can is an example of a container whose walls are diathermic. (v) Closed and open system: In a closed system, energy may transfer the boundaries of system but mass does not cross the boundary, while in open system, both mass and energy transfer across the boundary of the system. (vi) An isolated system: hi this type of system neither the mass nor the energy can be exchanged with the surroundings. (vii) Equation of state: The relationship between the pressure, volume and temperature of the thermodynamical system is called equation of state. (viii) Properties: A property of a system is any abusable characteristic of the given system various properties of the system depend on the state of the system not on how that state have been reached. (xi) Intensive property of a system or those properties whose values does not depend upon the mass of the system. Eg: Pressure, temperature, viscosity etc., while extensive properties depend upon the mass of the system. Eg: Length, volume etc. (x) Equilibrium: A system is said to be in thermodynamic equilibrium when it does not lead to change its properties (macroscopic) and make balance with its surroundings. There, a system in mechanical, thermal and chemical equilibrium is said to be in thermodynamic equilibrium.   THERMODYNAMIC SYSTEM A thermodynamic system is described as a kind of a region available in space and this region is concentrated for the purpose of analysing a problem. The system is considered to be separated from surroundings (external to system) by the boundary of the system. The nature of the boundary may be real or imaginary and it is considered to be flexible i.e., it can change its shape or size. If we combine a system and its surroundings, then it constitutes the universe.         TYPES OF THERMODYNAMIC SYSTEMS: There are three types of thermodynamic systems: (a) Closed system: A thermodynamic system in which mass is not transferred across system boundary but energy may be transferred in and out of the system, is known as closed system. Mass in the piston - cylinder arrangement is the example of a more...

  Fluid Mechanics and Machinery   Fluid: Fluid is a substance which has the property tendency to flow under the action of shear and tangential forces. Liquids and gases both are fluids. Ideal and Real fluids:

• In ideal fluids, there is no viscosity and no surface tension and are incompressible.
• In real fluids, viscosity, surface tension together exist and are compressible along with density.

Classification of fluids: Fluids can be classified on the basis of the following: Based on density and viscosity (i) Ideal fluid: An ideal fluid is described as a fluid which is in compressible and also has zero viscosity and constant density. (ii) Real fluids: A real fluid is described as a fluid which is compressible and viscous by nature. The density of real fluid are variable and while in motion, an amount of resistance is always offered by these fluids. (iii) Newtonian fluids: Newtonian fluidss are denned as fluids those obey Newton's law of viscosity. The density of these fluids may be constant or variable. The viscosity is calculated according to Newton'.s law of viscosity as: \[\tau =\mu \frac{du}{dy}\] where,   \[\tau \]=shear stress \[\mu =\]viscosity of fluid \[du/dy=\]velocity gradient Examples are, water, ethyl alcohol, benzene etc. (iv) Non – Newtonion fluids: Non-newtonian fluids are defined as fluids those do not obey Newton's laws of viscosity. The density of these fluids may be constant or variable and the viscosity of these fluids does not remain constant. Examples are Gels, Solutions of polymers, pastes etc. (v) Compressible fluids: A compressible fluid is defined as the fluid which reduces its volume when an external pressure is applied. All the fluids available in nature are compressible. (vi) In–compressible fluids: Incompressible fluids are defined as the fluids whose density does not change when the value of pressure changes. There is no effect of pressure on the density of fluid. In these fluids, density remains constant and viscosity remains non-zero. (vii) Inviscid fluid: Inviscid fluid is the fluid which has zero iscosity and density may be constant or variable.   FLUID PROPERTIES

Density\[(\rho )\]: It is denned as mass per unit volume of substance.

\[\rho =\frac{m}{V}\]

Specific Weight\[(\omega )\]: It is defined as weight per unit volume of substance.

\[\omega =\frac{mg}{V}=\rho g\]

Relative density Specific gravity (Sg): It is defined as ratio of density of fluid to the density of standard fluid.

It may also be defined as the ratio of specific weight of the fluid to the standard weight of fluid.  \[\text{Sg=}\frac{\text{weogjt}\,\,\text{of}\,\,\text{fluid}}{\text{weight}\,\,\text{of}\,\,\text{standard}\,\,\text{fluid}}\] \[\text{Sg=}\frac{\text{Density}\,\,\text{of}\,\,\text{fluid}}{\text{Density}\,\,\text{of}\,\,\text{standard}\,\,\text{Fluid}}\] Ex: oil of Sg of 0.8\[\Rightarrow {{\rho }_{oil}}=800\,\,kg/{{m}^{3}}\] Specific volume (v):                                  It is expressed as the volume per unit mass of fluid. \[v=\frac{V}{m}=\frac{1}{\rho }\]

Compressibility \[(\beta )\]

Hydrostatic law: It states that rate of increase of pressure in a vertical direction is equal to weight density of fluid at that point. Mathematically, pressure head (h)\[(h)=\frac{\rho }{\rho g}\] \[\beta =\frac{-\frac{dV}{V}}{dp}=\frac{1}{\rho }\,\,\frac{d\rho }{dp}\] Liquids are highly incompressible.\[\therefore \,\frac{d\rho }{dp}=0\]   Gases are highly compressible as \[P\propto \rho more...

Production Engineering PRODUCTION TECHNOLOGY Technology is the process of applying the finding of science and other forms of enquiry to applied situations. Production technology therefore involves applying the work of researchers to develop new products and processes.   Production Engineering Manufacturing or Production Engineering is the subset / specialization of a Mechanical Engineering. Mechanical Engineering with the focus only on Machine Tools, Materials Science, Tribology, and Quality Control is known as Manufacturing Engineering. Professional manufacturing engineers are responsible for all aspect of the design, development, implementation, operation and management of manufacturing system. Manufacturing is the most important element in any engineering process & Manufacturing Engineers are key personnel in many organization. The manufactured products range from aero planes, turbines, engines and pumps to integrated circuits and robotic equipment.   What does a Production Engineer do? Production Engineers work towards Choosing machinery and equipments for the particular manufacturing process Production Engineers will be planning & scheduling the production in any manufacturing industry.[E.g. Automobile Manufacturing industry]. Production Engineers will be programming the CNC machines to produce engineering components such as gears, screws, bolts, etc They are responsible for quality control, distribution and inventory control.   Top Sectors for Production Engineers to work

Research Labs

Manufacturing sector

Communication sector

Transportation

Banking

Pharmaceuticals

Finance

Travel

Semiconductor

e-business

Sports

Health

Information Technology

  Production Engineering covers two domains: (a) Production or Manufacturing Processes (b) Production Management   (a) Manufacturing Processes: This refers to science and technology of manufacturing products effectively, efficiently, economically and environment-friendly through

• Application of any existing manufacturing process and system
• Proper selection of input materials, tools, machines and environments.
• Improvement of the existing materials and processes
• Development of new materials, systems, processes gad techniques

All such manufacturing processes, systems, techniques have to be

• Technologically acceptable
• Technically feasible
• Economically viable
• Eco-friendly

  (b) Production Management: This is also equally important and essential in the manufacturing world. It mainly refers to planning, coordination and control of the entire manufacturing in most profitable way with maximum satisfaction to the customers by best utilization of the available resources like man, machine, materials and money. It may be possible to manufacture a product of given material and desired configuration by several processes or routes as schematically indicated in Fig. below Processes Input (raw material) Output (product) Processes   Fig: Possibility of manufacturing in number of routes.   Broad classification of Engineering Manufacturing Processes: It is extremely difficult to tell the exact number of various manufacturing processes existing and are being practiced presently because a spectacularly large number of processes have been developed till now and the number is still increasing exponentially with the growing demands and rapid progress in science and technology. However, all such manufacturing processes can be broadly classified in four major groups as follows: (a)   Shaping or forming Manufacturing a solid product of definite size and shape from a given material taken in three possible states: in solid more...

Automobile   Automobile engineering Automobile engineering, along with aerospace engineering and marine engineering, is a branch of vehicle engineering, incorporating elements of mechanical, electrical, electronic, software and safety engineering as applied to the design, manufacture and operation of motorcycles, automobiles and trucks and their respective engineering subsystems. It also includes modification of vehicles. Manufacturing domain deals with the creation and assembling the whole parts of automobiles is also included in it. The automotive engineering field is research -intensive and involves direct application of mathematical models and formulas. The study of automotive engineering is to design, develop, fabricate, and testing vehicles or vehicle components from the concept stage to production stage. Production, development, and manufacturing are the three major functions in this field.   Automobile Engineering Glossary A-Pillar - Pillar that joins the windshield to the front-most side windows Automatic Transmission - Automatic transmission system within a vehicle will automatically change gears within the transmission in response to the vehicle speed. AWD (All-Wheel Drive) - All wheel drive vehicles have a percentage of power sent to all wheels on the vehicle for propulsion. Axial - Forces or direction that is applied along the axis. If you picture a wheel on a car, axial would be the direction the axle is running, though the center of the wheel. Axis to dash - The relationship between the front wheels and the windshield of a vehicle which varies depending on whether the vehicle is front or rear wheel drive. Backlash - A reaction or recoil between parts that do not fit together properly, slop in mechanical system usually in gear that results in parts not fitting together as they should. (Usually a negative effect) Beltline - Line from the hood that runs below the bottom edge of the windows and ends at the trunk. Body - Outer portions of a vehicle (excluding the chassis) including, fiberglass, metal, etc. that form the outer shell of the vehicle. Body In White (BIW) - This is an industry term that describes the metal body of the car prior to any assembly or paint job applied. The Body in White is the product that comes directly from the body shop in an automotive assembly plant. Body wide line - Lateral lines where the maximum width of the vehicle can be measured (mirrors excluded). Bone line - (similar to swage line, feature line or character line) - A hard, positive only, linear peak in the body of a vehicle that even though it is not a structural feature, can impact the performance of a vehicle. Boss - A Boss is a piece of material that protrudes from the surface of the work space and is used to precisely locate another part so that they operate together correctly. Bottleneck - A bottleneck is the slowest station in the assembly process that determines the overall production rate. B-pillar - pillar next to the front seat occupant’s heads broken edge-broken edge describes a condition where the more...

Speed and Velocity   REST AND MOTION Rest:  When position of a body does not change with time it is said to be in state of rest.                 Motion: When position of a body changes with time it is said to be in state of motion. Rest and motion are relative terms. (i) Absolute motion: The motion of a body with respect to a body which is at complete rest is called absolute motion which is impossible. (ii) Relative motion: The motion of a body with respect to a body which is at rest relative to the body is called relative motion.   MOTION IN ONE, TWO AND THREE DIMENSIONS Motion in One Dimension An object moving along a straight line or path is said to have dimensional motion, also known as rectilinear motion. Examples Motion of a bus on a straight road and motion of a train on a straight track, an object dropped from a certain height above the ground, etc.   Motion in Two Dimensions An object moving in a plane is said to have two dimensional motion, Examples: Motion of an insect on a floor, earth revolving around the sun, a billiard ball moving over the billiard table, etc.   Motion in Three Dimensions An object moving in space is said to have three dimensional motion Examples: Motion of a Kite. motion of a flying aeroplane or bird, etc.   POSITION, PATH LENGTH AND DISPLACEMENT   Position The position of any particle can be given as follows: In cartesian co-ordianate form: The position of any particle is resented by co-ordinates (x, y, z) or position vector\[(\overrightarrow{r})\]. If a particle is located at point A in frame of reference x, y, z then the position of particle will be \[\overrightarrow{r}=x\,\hat{i}+y\,\hat{j}\,+z\,\,\hat{k}\] In polar form: \[x=r\cos \theta ;\,\,y=r\sin \theta \] \[\overrightarrow{r}=r\cos \theta \,\hat{i}\,+r\sin \theta \,\hat{j}\]   Path Length or Distance The length of the actual path between initial and final positions of a particle in a given interval of time is called distance covered by the particle. Distance is the actual length of the path. It is the characteristic property of any path i.e. path is always associated when we consider distance between two positions. Characteristics of distance (i) It is a scalar quantity (ii) It depends on the path (iii) It never reduces with time. (iv) Distance covered by a particle is always positive and can never be negative or zero. (v) Dimension: \[\left[ M{}^\circ LT0 \right]\] (vi) Unit: In C. G S. centimetre (cm), in S.I. system, metre (m).   Displacement The shortest distance from the initial position to the final position of the particle is called displacement                    Position vector of Aw.r.t. O=\[\overrightarrow{OA}\] \[\Rightarrow \]   \[\overrightarrow{{{r}_{A}}}={{x}_{1}}\,\,\hat{i}+{{y}_{1}}\,\,\hat{j}+{{z}_{1}}\,\,\hat{k}\] Position vector of B w.r.t. O\[=\overrightarrow{OB}\] \[\Rightarrow \]   \[\overrightarrow{{{r}_{B}}}={{x}_{2}}\,\,\hat{i}+{{y}_{2}}\,\,\hat{j}+{{z}_{1}}\,\,\hat{k}\] Displacement \[=\overrightarrow{AB}=({{x}_{2}}-{{x}_{1}})\,\,\hat{i}+({{y}_{2}}-{{y}_{1}})\,\,\hat{j}+({{z}_{2}}-{{z}_{1}})\,\,\hat{k}\] \[\Delta \overrightarrow{r}=\Delta x\,\,\hat{i}+\Delta y\,\,\hat{j}+\Delta z\,\,\hat{k}\]                           Characteristics of displacement   (i) It is a vector quantity. (ii) The displacement of a particle between any two points is equal more...

Mass, Weight and Density   Mass The mass (m) of a body of matter is quantitative measure of its inertia i.e., its resistance to a change in the state of rest or motion of the body, when a force is applied.

• SI unit of mass is the kilogram (kg). It is a scalar quantity.
• The greater the mass of a body, the smaller the rate of change in motion.

Inertia is the property of a mass which resists change from its states of rest or motion.

• The inertia of an object refers to the reluctance of the object to start moving if it is stationary in the first instance or the reluctance of the object to stop moving if it rs moving in the first instance.
• When a body of matter is stationary, it needs a force to make it start moving. The bigger the mass, the bigger the force needed. We say that masses have inertia: a reluctance to start moving.

Volume (V) is defined as the amount of space occupied by a three-dimensional object as measured in cubic units.

• SI unit of volume is meter cube .It is a scalar quantity.

  Weight The weight of an object is defined as the force of gravity on the object and may be calculated as the mass times the acceleration of gravity, w = mg. Since the weight is a force, its SI unit is the Newton. For an object in free fall, so that gravity is the only force acting on it, Then the expression for weight follows from Newton's second law. The value of g allows us to determine the net gravity force if it were in freefall and that net gravity force is the weight. Another approach is to consider "g" to be the measure of the intensity of Ac gravity field in Newtons/kg at our location. We can view the weight as a measure of the mass in kg times the intensity of the gravity field, 9.8 Newton's/kg under standard conditions.   Density Density (p) is defined as the mass of a substance per unit volume. 

• SI unit of density is kilograms per meter cube \[(kg\,\,{{m}^{-3}})\] It is a scalar quantity.
• Another common unit of density is \[g\,\,c{{m}^{-3}}g\,\,c{{m}^{-3}}.1000\,kg\,{{m}^{-3}}\]\[=1\,\,g\,\,c{{m}^{-3}}1000\,kg\,{{m}^{-3}}=1\,\,g\,\,c{{m}^{-3}}\]
• \[\rho =m\,V\]
• The density of a substance does not change as we move from place to place as the mass and volume does not depend on the gravitational acceleration of the point that the object is at.

There are two kinds of density, "weight density" and "mass density". We will only use mass density and when we say: "density", its means "mass density". The metric system was designed so that water will have a density of one gram per cubic centimeter or 1000 kilograms per cubic meter. Lead is about 10 times as dense as water and Styrofoam is about one tenth as dense as water.   Fluid more...

Unit and Measurements   PHYSICAL QUANTITIES Those quantities which can describe the laws of physics and possible to measure are called physical quantities. A physical quantity is that which can be measured. Physical quantity is completely specified; If it has

	Only numerical value Ex. Refractive index, dielectric constant etc.
	Only magnitude ex, Mass, charge etc.
	Magnitude and direction Displacemnt, torque etc.

Types of physical Quantities     The physical quantities which do not depend upon other Physical quantities are called fundamental quantities. In M.K.S System the fundamental quantities are mass, length and time In standard International system the fundamental quantities are mass, length, time, temperature, illuminatig power current and amount of substance, The physical quantities which depend on fundamental quantities are called derived quantities e, g. speed, acceleration, force, etc   UNITS The unit of a physical quantity is the reference standard used to measure it. For the measurement of a physical quantity a definite magnitude of quantity is taken as standard and the name given to this standard is called unit.   Properties of Unit (a) The unit should be well-defined. (b) The unit should be of some suitable size. (c) The unit should be easily reproducible. (d) The unit should not change with time. (e) The unit should not change with physical conditions like pressure, temperature etc. (f)   The unit should be universally acceptable.   Types of Units

Fundamental Units

The units defined for the fundamental quantities are called fundamental or base units.   Base quantities and their SI unit

• Unit of mass = kilogram

One kilogram is defined as the mass of a platinum iridium cylinder kept in National Bureau of Weights and Measurements, Paris.

• Unit of length = metre

The distance travelled by light in vacuum in 1/299,792,458 second or it is equal to 1650763.73 wavelength emitting From \[K{{r}^{86}}\]

• Unit of time = second

The time interval in which Cesium-133 atom vibrates 9, 192, 631, 770times.

• Unit of temperature = kelvin

It is defined as the (1/273.16) fraction of thermo dynamic temperature of triple point of water. Triple Point of Water is the temperature at which ice, water and water vapours co-exist.

• Unit more...

Engineering Drawing   ENGINEERING DRAWING Engineering drawing is a type of technical drawing, created within the technical drawing discipline, and is used to define the requirements for engineered items. It is also a graphical language that communicates ideas and information from one mind to another. The purpose of engineering drawing is to capture all the geometric features of a product or a component accurately and unambiguously. Its end goal is to convey the information that will allow a manufacturer to produce that component.   ENGINEERING DRAWINGS: COMMON FEATURES Geometry – shape of the object; represented as views and how the object will look when viewed from various standard directions , such as front, top, side, etc. Dimensions – size of the object captured in accepted units. Tolerances – allowable variations for every dimension. Material – represents what the item is made of. Finish – specifies the surface quality of item, functional or cosmetic. Example of an Engineering Drawing Here is an example of an engineering drawing (an isometric view of the same object is show bellow). The different line types are colored for clarity.

• Black = object line and hatching
• Red = hidden line
• Blue = center line of piece or opening

Magenta = phantom line or cutting plane line TYPES OF DRAWING    Isometric Drawing Representation of the object in figure below is called an isometric drawing. This is one of a family of three-dimensional views called pictorial drawings. In an isometric drawing, the object's vertical lines are drawn vertically, and the horizontal lines in the width and depth planes are shown at 30 degrees to the horizontal. When drawn under these guidelines, the lines parallel to these three axes are at their true (scale) lengths. Lines that are not parallel to these axes will not be of their true length. Figure An Isometric Drawing A engineering drawing should show everything: beaa complete understanding of the object should be possible from the drawing- If the isometric drawing can show all details and all dimensions on one drawing, it is ideal. One can pack a great deal of information into an isometric drawing. However, if the object in figure above had a hole on the back side, it would not be visible using a single isometric drawing. In order to get a more complete view of the object, an orthographic projection may be used.   Orthographic Drawing Imagine that we have an object suspended by transparent threads inside a glass box, as in figure below.   Figure - The block suspended in a glass box Then draw the object on each of three faces as seen from that direction. Unfold the box (figure below) and you have the three views. We call this an "orthographic" or "multi-view" drawing. Figure - The creation more...

  Computer Memory   The computer memory is one of the most important elements in a computer system. It stores data and instructions required during the processing of data and output results. Storage may be required for a limited period of time, instantly or for an extended period of time. It also relates to many devices that are responsible for storing data on a temporary or a permanent basis.   Memory Hierarchy The hierarchical arrangement of storage in current computer architectures is called the memory hierarchy. The computer uses a hierarchy of memory that is organised in a manner to enable the fastest speed and largest capacity of memory as shown in figure.   Parameters of Memory                Some related parameters of memory are as follow                           (i) Storage Capacity It is representative of the size of memory. The capacity of internal memory and main memory can be expressed in terms of number of words or bytes. (ii) Access Modes A memory is comprised of various memory locations. The information from these memory locations can be accessed randomly, sequentially and directly. (iii) Access Time The access time is the time required between the desired modes for a read or write operation till the data is made available or written at the desired location. (iv) Physical Characteristics In this respect, the devices can be categorised into four main categories as electronic, magnetic, mechanical and optical. (v) Permanence of Storage Its permanence is high for future use in magnetic materials.   Types of Memory In general, the memory is classified into two categories as follows (a) Primary memory or Main memory (b) Secondary memory or Auxiliary memory   Primary Memory The memory unit that communicates directly with the CPU is called main memory or the internal memory. The primary memory allows the computer to store data for immediate manipulation and to keep track of what is currently being processed. It is volatile in nature, it means that when the power is turned OFF, the contents of the primary memory are lost forever. Primary memory can be further classified in two categories which are as follows   Random Access Memory It is also known as read/write memory that allows CPU to read as well as write data and instructions into it. RAM (Random Access Memory) is used for the temporary storage of input data, output data and intermediate results. There are two categories of RAM as follows (a) Dynamic RAM (DRAM) It is made up of memory cells where each cell is composed of one capacitor and one transistor. DRAM must be refreshed continually to store information. DRAM is slower, less expensive and occupies less space on the computer's motherboard. (b) Static RAM (SRAM) It retains the data as long as power is provided to the memory chip. It needs not be refreshed periodically. SRAM uses multiple transistors for each memory cell. It does not use more...

  Introduction to Computer   A computer is an electronic machine that accepts data from the user, processes the data by performing calculations and operations on it and generates the desired output as a result. The term computer is derived from the Latin word 'computare' which means 'to compute'.   Generally, computer is the combination of Hardware and Software which converts data into information. Computer operates on set of instructions only, they cannot think as human being. Computer has an ability to store and execute set of instructions called program which makes it extremely distinguishable and versatile than calculators. Computer makes people's lives easier and more comfortable.     Functioning of a Computer Computer Performs four basic functions -which are as follows

Input Information or data that is entered into a computer is called input. It sends data and instructions to the Central Processing Unit (CPU).

Processing It is the sequence of actions taken on data to convert it into information which is meaningful to the user. It can be calculations, comparisons or decisions taken by the computer.

Output It makes processed data available to the user. It is mainly used to display the desired result to the user as per input instructions.

Storage It stores data and programs permanently. It is used to store information during the time of program execution and possible to get any type of information from it.

  Features of Computer The key features of computer are as follows

Speed The computer can process data very fast at the rate of millions of instructions per second.

Accuracy Computers provide a high degree of accuracy. They respond to the user as per the input instructions.

Storage Capacity Computers are capable to store huge amount of data which depends on the capacity of hard disk.

Versatility Computers can do different types of work simultaneously. They can perform multiple tasks at a same time.

Automatic Once the instruction to do any work is given to the computer, the computer does its work automatically by itself.

Diligency Unlike human beings, a computer is free from monotony, tiredness, lack of concentration, etc and can work for hours without creating any errors.

Secrecy Leakage of information is reduced by creating login system with password protection.

Reliability Computer are more reliable than human beings. Computers always produce exact results. The possibility of errors occur only if the input is wrong, i.e. the computers never make mistakes of their own accord.

Plug and Play Computers have the ability to automatically configure a new hardware and software component.

   Terms Related to Computer 

Hardware It is the collection of physical elements that constitute a computer system. It is a comprehensive term for all the physical parts of a computer, e.g. display screens, disks, keyboards, etc.

Software It is more...