P2213_HW03_solns_Fall2008 - - 1 - Physics 2213 HW #3...

Info iconThis preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: - 1 - Physics 2213 HW #3 Solutions Fall 2008 18.41 [Heat Capacities] 5 /2 V C R = for a diatomic ideal gas and 3 /2 V C R = for a monatomic ideal gas. (a) ( 29 5 2 V Q nC T n R T = = ( 29 5 2 (2.5 mol) (8.3145 J/mol K)(30.0 K) 1560 J Q = = (b) ( 29 3 2 V Q nC T n R T = = ( 29 3 2 (2.5 mol) (8.3145 J/mol K)(30.0 K) 935 J Q = = More heat is required for the diatomic gas; not all the heat that goes into the gas appears as translational kinetic energy, some goes into energy of the internal motion of the molecules (rotations). 19.23 [Auto Engine R&D] For constant volume, V Q nC T = , whereas for constant pressure, p Q nC T = . For nitrogen, 20.76 J/mol K V C = and 29.07 J/mol K p C = . (a) The pV-diagram is sketched in figure (a) below. 645 J 167.9 K (0.185 mol)(20.76 J mol K) V Q T nC = = = and 948 K . T = (b) The pV-diagram is sketched in figure (b) below. 645 J 119.9 K (0.185 mol)(29.07 J mol K) p Q T nC = = = and 900 K . T = At constant pressure some of the heat energy added to the gas leaves the gas as expansion work and the internal energy change is less than if the same amount of heat energy is added at constant volume. T is proportional to . U 19.34 [Ferrari Engine] (a) In the process the pressure increases and the volume decreases. The pV-diagram is sketched below. - 2 - (b) For an adiabatic process for an ideal gas 1 1 1 1 2 2 , TV T V -- = 1 1 2 2 , p V...
View Full Document

This note was uploaded on 10/25/2008 for the course PHYS 2213 taught by Professor Perelstein,m during the Fall '07 term at Cornell University (Engineering School).

Page1 / 4

P2213_HW03_solns_Fall2008 - - 1 - Physics 2213 HW #3...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online