Thermodynamics Revision Sheet
Thermodynamics Revision Sheet
Temperature
TF=9/5 TC + 32° TC = TK - 273.15 K The pressure,volume and temperature in kelvin of such gases obey the equation PV=nRT ----(1) Thermal expansion ΔL=αLΔT Specific Heat Capacity=ΔQ/mΔT |
Gas Laws
Boyles Law: PV=constant Charles Law : V/T=constant Dalton Law of Partial Pressure: P=P1 + P2 +P3 Root mean Square Velocity Vrms=√3RT/M Mean Velocity Vm=√8RT/πM Most Probable Velocity V=√2RT/M Also Vrms > Vm > V Average kinetic Energy of Gas=3/2nRT |
First law of Thermodynamics
ΔU=Q-W Gas Processes Isothermal Process : PV=constant ,ΔU=0,Q=W,Molar Specific Heat=infinity Adaibatic Process : PVy=constant,Q=0,ΔU=-W,Molar Specific Heat=zero Polytropic Process : PVn=constant,Molar Specific Heat=[R/(y-1) + R/(1-n)] Volume Constant : P/T=constant W=0,ΔU=Q,Molar Specific Heat=Cv Pressure Constant : V/T=constant ΔU=Q-W ,Molar Specific Heat=CP Internal energy depends on Temperature. So for same temperature change ΔT nCvΔT=Q1-W1=Q2-W2=Q3-W3 Molar Specfic Heat Capacity of any process is given by C=Cv + Pdv/ndT where n is no of moles of the gas Workdone by Gas= ∫PdV |
Heat Conduction
Q=-KAdT/dx Wein displacement lawλT4=Constant Stefan's Law Q=eσT4 dT/dx=b(T-Ts) |
Problem
Solving tips
1. Net Heat flow at a junction is Zero
2. Internal Energy does not depend on the
path
3. Internal Energy in a cyclic Process is zero
4. Heat is positive when given to the system
and negative when taken out of the system
5. Workdone by the system on the surrounding
is positive while the workdone on the system by the surrounding is megative
|
0 comments:
Post a Comment