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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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Gas law,charles law,boyle law,avogadro law,joule law,gay-lusac law,adiabetic free expansion,throttling process,efficiency engine(air standard,thermal,relative,mechanical,overal)

                      THERMODYNAMIC
GAS LAW:we are study about gas,we have also knowing 4 parameters of gas.
  P = Pressure
  V = Volume
  n = moler no
  T = Temperature
After a long time experiment we get a equation of gas law.
        pV = mRT
how we get this,we discussed in below,
Boyle's law: Boyle said that p ∝ 1/V .T = contant.
Charles' law: Charles said  V ∝ T. p = constant.(all perfect gas change in vvolume by 1/273 of its original volume at 0°C for every 1°c change in temperature).
Gay-lussac law: p ∝ T, (V= constant)
Avogadro's law: Equal volume of all gases under the similar condition temperature and pressure contain the same no of molecules.(moleculer weight expressed in gm)
joule's law: Change of internal energy dU ∝ dT
 perfect gas: A perfect gas is one which obey 5 gas law in all concondition of temperature and pressure.
       General gas equation:
   p1V1/T 1=p2V2/T2 =p3V3/T3 = constant
     Charestristic gas equation:
       pV = mRT = n.MRT
Where (m = mass of gas)
     n = no. Of moles of gas.
     R = gas constant.
     M = molecular weight.(287 J/kg/°K)
UNIVERSAL GAS CONSTANT OR MOLAR WEIGHT : 8314 J/Kg mole/°k
 Note: R = Cp/Cv
 Cp — Cv= R/J (R is also sometimes denoted by Ï’.
Adiabetic expansion: An adiabetic expansion in which gas expand with out no work done.
     Î”U = Q + W
    Î”U = 0+0
    Î”U = 0[ when temperature in constant ]
Throttling process: Fluid expand high to low pressure without doing any work (enthalpy=0).
  
Efficiency of engine;
   Air standard efficiency:Actually,it is the ideal efficiency,it use to compareing to various cycle,it is defined the ratio of the ideal workdone to heat supplied.
  Thermal efficiency:It is the ratio of the indicated work done to heat supplied of an engine.
  Relative efficiency:is the ratio of thermal eefficiency to air standard efficiency.
  Mechanical efficiency:Brake or actual workdone/Indicated work.
  Overall efficiency:Brake workdone/Heat supplied.its also call brake tharmal efficiency.

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