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Theory of machine| part -1

Kinematics links - Every part of machine which have relative motion to another part.   → The link should be resistance body.   What is resistant body? →Under the action of force it can transfer motion and power. Kinematics links →1. Rigid links     2. Flexible links     3. Fluid links Rigid links - There is no deformation.   Ex - piston,connecting rod Flexible links - Deformation is allowed under permissible limits. Ex - Belt drive Fluid links - A fluid link is one that is deformed by having fluid in a closed vessel and the motion is transmitted through the fluid by pressure. Ex - Hydraulic press   Types of links - 1. Singular 2. Binary 3. Ternary 4. Quaternary links
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Details about energy.what is heat?what is enthalpy? Change in enthalpy.what is entropy?difference between 1st law and 2nd lawhttps://engineerapk.blogspot.com/2017/11/details-about-energywhat-is-heatwhat-is.html

                    THERODYNAMIC
Energy:Capacity of to doing work.
Types of energy
  1.potential energy(P.E.): Energy due to position,consumstion or condition.
  2.Kinetic energy (K.E.):Energy of motion.
       K.E. = 1/2 mV2
     m = mass(S.I unit Kg)
     V = velocity(S.I unit N/m)
  S.I. Unit for enegy (E) = Kg.m^2/S2
potential energy unit same as kinetic energy.
    1 j = kg m^2/s^2
              ENERGY EXCHANGE
     System+Surrounding = Universe.
Internal energy is contained in a body is measured very hard.
From 0th law,hot body release energy to cold body when they are contact.

HEAT: Energy transfer difference by temperature.

Enthalpy:Enthalpy is a total heat content of a system.
       H = U+pV       [ U = internal energy ]
Change in ethalpy:
                    

          ΔH = change in enthalpy
Specific Heat: Heat supplied =m༝Δt༝c
 m = mass of the material.
 Δt = temperture raised of material.
 C = constant[ depents on material]
 If m = 1unit, Δt = 1unit, Q = C
Amount of heat require to raise temperature of unit mass by temperature,is call specific heat.
Cp = specific heat capacity at constant pressure.
Cv = specific heat capacity at constant volume.
Second law of thermodynamics:
Clausius statement: heat doesn't flow automatically cold to hot object.
Kelvin-plank statement: heat cannot converted in 100% work in reversible cyclic process.
Whenever heat flow,clausius found a simple ratio,
    Ratio =Total heat gain or loss/Temperature which gain or loss
    Below example,
                              

In reversible process,
     Ratio(total) = system(total)+ surrounding(surrounding) = 0
Here,the ratio known as Entropy(ΔS).
 ΔS(total) = Δs(total)+ Δs(total) = 0 ( reversible process )
 ΔS(total) = Δs(total) + Δs(total) > 0 ( irreversible process )
Actually, 2th Law said that total change in entropy is equal or greater than zero.
Difference between first & second laws of thermodynamic: First law is concerned with quality and sum total of energy,bt second law explain difference between heat and work, exergy and anergy.
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