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It is the temperature below which the tendency of a MATERIAL to fracture increases RATHER than forming. Below this temperature the material loses its ductility. It is also called NIL Ductility Temperature

It is the temperature below which the tendency of a material to fracture increases rather than forming. Below this temperature the material loses its ductility. It is also called Nil Ductility Temperature

TORQUE is defined as a FORCE applied to an object that results in ROTATIONAL motion.

Torque is defined as a force applied to an object that results in rotational motion.

It is the ratio of the number of REVOLUTIONS of the PINION gear to ONE REVOLUTION of the idler gear.

It is the ratio of the number of revolutions of the pinion gear to one revolution of the idler gear.

6 is the type CODE, which shows it is a single-row ball bearing, 2 is the series, MEANS light, 03 is the bore, which is 17 mm and ZZ is the suffix meaning DOUBLE shielded bearing.

6 is the type code, which shows it is a single-row ball bearing, 2 is the series, means light, 03 is the bore, which is 17 mm and ZZ is the suffix meaning double shielded bearing.

Otto cycle can be EXPLAINED by a pressure volume RELATIONSHIP diagram. It shows the functioning cycle of a four stroke engine. The cycle starts with an INTAKE stroke, closing the intake and MOVING to the compression stroke, starting of combustion, power stroke, heat exchange stroke where heat is rejected and the exhaust stroke. It was designed by Nicolas Otto, a German engineer.

Otto cycle can be explained by a pressure volume relationship diagram. It shows the functioning cycle of a four stroke engine. The cycle starts with an intake stroke, closing the intake and moving to the compression stroke, starting of combustion, power stroke, heat exchange stroke where heat is rejected and the exhaust stroke. It was designed by Nicolas Otto, a German engineer.

PS is Pferdestarke, the GERMAN UNIT for HORSEPOWER.

PS is Pferdestarke, the German unit for Horsepower.

1 BTU is EQUAL to 1055.056 JOULES.

1 BTU is equal to 1055.056 joules.

A Newtonian fluid possesses a LINEAR stress strain relationship curve and it PASSES through the ORIGIN. The fluid PROPERTIES of a Newtonian fluid do not change when any force ACTS upon it.

A Newtonian fluid possesses a linear stress strain relationship curve and it passes through the origin. The fluid properties of a Newtonian fluid do not change when any force acts upon it.

Reynolds number is the RATIO of inertial force and viscous force. It is a DIMENSIONLESS number. It DETERMINES the type of fluid flow.

Reynolds number is the ratio of inertial force and viscous force. It is a dimensionless number. It determines the type of fluid flow.

Proportional LIMIT, elastic limit or yield POINT, ultimate STRESS and stress at failure.

Proportional limit, elastic limit or yield point, ultimate stress and stress at failure.

When a MOMENT is APPLIED to BEND an ELEMENT, a bending moment exists in the element.

When a moment is applied to bend an element, a bending moment exists in the element.

WET bulb temperature is measured in a wet bulb thermometer by covering the bulb with a WICK and wetting it with water. It corresponds to the dew POINT temperature and relative HUMIDITY.

Wet bulb temperature is measured in a wet bulb thermometer by covering the bulb with a wick and wetting it with water. It corresponds to the dew point temperature and relative humidity.

The entropy of the UNIVERSE INCREASES over TIME and MOVES TOWARDS a maximum value.

The entropy of the universe increases over time and moves towards a maximum value.

ACCORDING to the Hess LAW the energy transfer is simply INDEPENDENT of the path being followed. If the reactant and the product of the whole process are the same then same amount of energy will be dissipated or ABSORBED.

According to the Hess law the energy transfer is simply independent of the path being followed. If the reactant and the product of the whole process are the same then same amount of energy will be dissipated or absorbed.

Diamond.

Diamond.

Gibbs HELMHOLTZ formula is the formula which forms the link between the thermodynamics and ELECTROMAGNETISM.

∆Hs/R = [∂ lnp /∂ (1/T)]X

where: x – mole fraction of CO2 in the liquid phase 
p – CO2 partial PRESSURE (kPa) 
T – temperature (K) 
R – universal gas CONSTANT 
α – mole ratio in the liquid phase (mole CO2 per mole of amine)

Gibbs Helmholtz formula is the formula which forms the link between the thermodynamics and electromagnetism.

∆Hs/R = [∂ lnp /∂ (1/T)]x

where: x – mole fraction of CO2 in the liquid phase 
p – CO2 partial pressure (kPa) 
T – temperature (K) 
R – universal gas constant 
α – mole ratio in the liquid phase (mole CO2 per mole of amine)

It was being designed by CARNOT and LET me TELL you that Carnot engine is an imaginary engine which follows the Carnot CYCLE and provides 100% efficiency.

It was being designed by Carnot and let me tell you that Carnot engine is an imaginary engine which follows the Carnot cycle and provides 100% efficiency.

YES DEFINITELY the BOILER is a CLOSED SYSTEM.

Yes definitely the boiler is a closed system.

ACCORDING to the laws of CONSERVATION of energy, “energy can NEITHER be created nor be destroyed. It can only be transformed from ONE form to ANOTHER.”

According to the laws of conservation of energy, “energy can neither be created nor be destroyed. It can only be transformed from one form to another.”

There are three laws of the THERMODYNAMICS.

1. First Law : Energy can be neither CREATED nor destroyed. It can only change forms.In any PROCESS in an isolated system, the total energy remains the same.
2. Second Law : When two isolated systems in separate but nearby regions of space, each in thermodynamic equilibrium in itself, but not in equilibrium with each other at first, are at some time allowed to interact, breaking the isolation that separates the two systems, and they exchange matter or energy, they will eventually reach a mutual thermodynamic equilibrium. The sum of the entropies of the initial, isolated systems is less than or equal to the entropy of the final exchanging systems. In the process of reaching a new thermodynamic equilibrium, entropy has increased, or at least has not decreased.
3. Third Law : As temperature approaches ABSOLUTE zero, the entropy of a system approaches a MINIMUM.

There are three laws of the thermodynamics.

All the mechanical ENGINEERING systems are STUDIED with the HELP of THERMODYNAMICS. Hence it is very IMPORTANT for the mechanical engineers.

All the mechanical engineering systems are studied with the help of thermodynamics. Hence it is very important for the mechanical engineers.

The function of FLYWHEEL is to STORE the energy/power PRODUCED during the power stroke of an engine and this stored energy is USED during remaining stroke to make piston up and down during working of engine while governor tries control the speed of an engine due to variation in load. It does this work by reducing or increasing the amount of fuel PASSING to the engine.

The function of flywheel is to store the energy/power produced during the power stroke of an engine and this stored energy is used during remaining stroke to make piston up and down during working of engine while governor tries control the speed of an engine due to variation in load. It does this work by reducing or increasing the amount of fuel passing to the engine.

• There always a debate between differentiation of pipe and tube. Pipe is always designated by its Inside Diameter (ID) because MAIN purpose of pipe is to carry fluid, while the 
• Tube is always designated by its Outside Diameter (OD). Pipe's thickness is sometimes called as schedule and tube's thickness is gauge.
• As PER the tolerance BASIS, TUBES requires higher tolerances as to that of pipe and tubes are more costlier in manufacturing compared to pipe production. 

Not possible. Because thermal radiation BECOMES only zero at absolute zero TEMPERATURE which can NEVER be attained by the third law of THERMODYNAMICS.

Not possible. Because thermal radiation becomes only zero at absolute zero temperature which can never be attained by the third law of thermodynamics.

HEAT transfer deals with the energy analysis which in transition and and depends on the modes of heat transfer like CONDUCTION, convection and radiation or combination of any modes. Heat transfer deals in NON equilibrium DOMAIN and CONDITIONS while thermodynamics deals with study of system at equilibrium and does not depend on how heat transfer is calculated.

Heat transfer deals with the energy analysis which in transition and and depends on the modes of heat transfer like conduction, convection and radiation or combination of any modes. Heat transfer deals in non equilibrium domain and conditions while thermodynamics deals with study of system at equilibrium and does not depend on how heat transfer is calculated.

As per the second law of thermodynamics, any heat INPUT to the system (Heat engine) cannot be converted completely into useful WORK. Some energy is lost and that is CALLED 'UNAVAILABLE work'. The AMOUNT of unavailable work increases as the entropy increases.

As per the second law of thermodynamics, any heat input to the system (Heat engine) cannot be converted completely into useful work. Some energy is lost and that is called 'unavailable work'. The amount of unavailable work increases as the entropy increases.

A REAL gas BEHAVES like an ideal gas in LOW PRESSURE and high temperature conditions.

A real gas behaves like an ideal gas in low pressure and high temperature conditions.

When a material is COMPRESSED in one DIRECTION, it usuallytends to EXPAND in the other two DIRECTIONS perpendicular tothe direction of compression. This phenomenon is CALLED the Poisson effect. Poisson’s ratio is a measure of the Poisson effect.

For rubber = 0.5
For steel = 0.288
For wood < 0.2

Thus Poisson’s ratio is higher in RUBBER.

When a material is compressed in one direction, it usuallytends to expand in the other two directions perpendicular tothe direction of compression. This phenomenon is called the Poisson effect. Poisson’s ratio is a measure of the Poisson effect.

For rubber = 0.5
For steel = 0.288
For wood < 0.2

Thus Poisson’s ratio is higher in RUBBER.

No, It will not WORK, as the Compression ratio of PETROL engine is 6 to 10 & that of Diesel engine is 15 to 22. THUS on such high compression, GASOLINE gets highly COMPRESSED & it may blast.

No, It will not work, as the Compression ratio of Petrol engine is 6 to 10 & that of Diesel engine is 15 to 22. Thus on such high compression, gasoline gets highly compressed & it may blast.

IMPROVING the surface finish by Polishing & PROVIDING RESIDUAL stress by SHOT peening.

Improving the surface finish by Polishing & providing residual stress by Shot peening.

Divide the shaft diameter SIZE by 5, it will give last two DIGIT of the bearing no. and according to type of load we have to CHOOSE the type of bearing and that will give prior NUMBER of the bearing.

Divide the shaft diameter size by 5, it will give last two digit of the bearing no. and according to type of load we have to choose the type of bearing and that will give prior number of the bearing.

NATURAL GAS (GASOLINE)… at 20 CELSIUS

Natural gas (Gasoline)… at 20 Celsius

DIFFERENTIAL MECHANISM

Differential mechanism

REAR WHEEL sprocket WORKS under the principle of ratchet and PAWL.

Rear wheel sprocket works under the principle of ratchet and pawl.

746.2 WATT

746.2 Watt

Engine specifications are different in different MANUFACTURES like as Bore Diameter (CC), Ignition timing. Also the EXHAUST PASSAGE TAKES more responsible for sound.

Engine specifications are different in different manufactures like as Bore Diameter (CC), Ignition timing. Also the exhaust passage takes more responsible for sound.

ds=dQ/T. Entropy is INVERSELY PROPORTIONAL to the temperature so, as temp. Increases, entropy decreases.

ds=dQ/T. Entropy is inversely proportional to the temperature so, as temp. Increases, entropy decreases.

This THERMODYNAMIC quantity states that the decrease in value during a process is equal to the useful work done by the system. It is denoted by G and the mathematical equation is:

G = H – TS

Where,

H = heat CONTENT 
T = absolute temperature 
S = entropy of the system

For isothermal process we have

G1 = H1 – TS1 for the initial state 
G2 = H2 – TS2 for final stage

Therefore,

G2 – G1 = (H2 – H1) – T(S2 – S1)

Now,

ΔG = G2 – G1 is the CHANGE in Gibbs free energy 
ΔH = H2 – H1 is the change in enthalpy of the system 
ΔS = S2 – S1 Is the change in entropy of the system

Thus the above equation becomes:

ΔG = ΔH – TΔS is known as Gibbs-Helmoholtz equation.

This thermodynamic quantity states that the decrease in value during a process is equal to the useful work done by the system. It is denoted by G and the mathematical equation is:

G = H – TS

Where,

H = heat content 
T = absolute temperature 
S = entropy of the system

For isothermal process we have

G1 = H1 – TS1 for the initial state 
G2 = H2 – TS2 for final stage

Therefore,

G2 – G1 = (H2 – H1) – T(S2 – S1)

Now,

ΔG = G2 – G1 is the change in Gibbs free energy 
ΔH = H2 – H1 is the change in enthalpy of the system 
ΔS = S2 – S1 Is the change in entropy of the system

Thus the above equation becomes:

ΔG = ΔH – TΔS is known as Gibbs-Helmoholtz equation.

1. Isolated system: A system that can neither exchange matter nor HEAT with the SURROUNDING is known as an isolated system.
   For example: Water PLACED in a VESSEL that is closed as WELL as insulated. 
2. Open system: A system that can exchange both matter and energy with the surrounding is said to be an open system.
   For example: A reaction taking place in an open vessel exchanges both energy and matter with the surrounding. 
3. Closed system: A system that exchanges only energy and not matter with the surrounding is said to be a closed system.
   For example: A reaction taking place in a closed metallic vessel.

1. Zeroth law: If any two SYSTEMS are in thermal equilibrium with the third system, then they are also in thermal equilibrium with each other. 
2. First law: First law of thermodynamic STATES that energy can neither be created nor be DESTROYED but it can only be converted from ONE form to another. 
3. SECOND law: This law states that “all processes in nature tend to occur with an increase in entropy and the direction of change always lead to the increase in entropy.” 
4. Third law: This law states that “The entropy of a perfect crystal of each element and a compound is zero at absolute zero.”

The third law of thermodynamics states that:

“The entropy of a PERFECT crystal of each element and a compound is zero at absolute zero.”

Limitations: If any disorder like IMPURITY or IMPERFECTION is found in a substance then the entropy of such crystal is non-zero at 0 K. For example: The entropy of pure carbon dioxide and nitric oxide is zero at 0K. This shows that there exists disorder in the arrangement of such molecules.

This law is applicable only to pure compounds. Thus we can say that, this law is not applicable to glass which is a supercooled liquid. It is also not applicable to amorphous substance and supercooled solutions.

Importance:

1. With the help of this law Thermodynamic properties can be calculated and chemical affinity can be MEASURED. 
2. This law helps in explaining the behaviour of solids at very low temperature.

The third law of thermodynamics states that:

“The entropy of a perfect crystal of each element and a compound is zero at absolute zero.”

Limitations: If any disorder like impurity or imperfection is found in a substance then the entropy of such crystal is non-zero at 0 K. For example: The entropy of pure carbon dioxide and nitric oxide is zero at 0K. This shows that there exists disorder in the arrangement of such molecules.

This law is applicable only to pure compounds. Thus we can say that, this law is not applicable to glass which is a supercooled liquid. It is also not applicable to amorphous substance and supercooled solutions.

Importance: