Lecture 3

Question 1

polytropic

Answer 1

approximation to reality - uses constant that tells you how gas behaves

Question 2

closed system polytropic

Answer 2

real gases during expansion and compression, pressure and volume are usually related pV^n = constant

Question 3

polytropic constant n describes

Answer 3

how the expansion relates to the temperature and pressure

Question 4

when polytropic constant n= 0

Answer 4

pressure is constant pV^0 = p = constant

work done at constant pressure

Question 5

when polytropic constant n= 1

Answer 5

T is constant ie PV= mRT

ie ideal gas equation

Question 6

when n= infinity

Answer 6

V is constant

Question 7

for isentropic process

Answer 7

n = cp/cv = gamma

Question 8

for perfect gas

Answer 8

pv = RT

Question 9

closed system u2-u1=

Answer 9

cv(T2-T1)

Question 10

pressure volume graph

Answer 10

diagram

Question 11

for isothermal process change in internal energy =

Answer 11

change in enthalpy as change in volume = 0 there

Question 12

isentropic process is a

Answer 12

adiabatic reversible one

Question 13

polytropic vs adiabatic

Answer 13

real vs ideal gas
for ideal n = gamma = cp/cv
for real gas n is variable dependent on the system