a) A gas is trapped in a piston-cylinder device. The initial pressure and temperature of the gas are 500 kPa and 300 K, respectively. The system undergoes an isothermal expansion process, in which 15KJ of boundary work is done by the gas and 3KJ of paddle-wheel work is done on the gas. Determine the amount heat transfer during this process. Explain the direction of the heat transfer. b) Air with a volume of 0.031 m³ is trapped in a piston-cylinder assembly at a temperature of 40°C and a pressure 102 kPa. The air is compressed adiabatically to a pressure 350 kPa. cr=0.718 kl/kg.k and c₂=1.00 kJ/kg. K Determine The work done during this process. c) As shown in Figure A1-c, a gas is contained in a piston-cylinder assembly. The mass and the cross-sectional area of piston are 3.20 kg and 35 cm², respectively. During heating, the spring is compressed and applies a force of 0.15 kN on the piston when the initial volume increased by 3 litres. Determine the final pressure in the cylinder and the work done by the gas during this process. 150 N =95 kPa -3.2kg 35 cm² Figure A1-c

a) A gas is trapped in a piston-cylinder device. The initial pressure and temperature of the gas are 500 kPa and 300 K, respectively. The system undergoes an isothermal expansion process, in which 15KJ of boundary work is done by the gas and 3KJ of paddle-wheel work is done on the gas. Determine the amount heat transfer during this process. Explain the direction of the heat transfer. b) Air with a volume of 0.031 m³ is trapped in a piston-cylinder assembly at a temperature of 40°C and a pressure 102 kPa. The air is compressed adiabatically to a pressure 350 kPa. cr=0.718 kl/kg.k and c₂=1.00 kJ/kg. K Determine The work done during this process. c) As shown in Figure A1-c, a gas is contained in a piston-cylinder assembly. The mass and the cross-sectional area of piston are 3.20 kg and 35 cm², respectively. During heating, the spring is compressed and applies a force of 0.15 kN on the piston when the initial volume increased by 3 litres. Determine the final pressure in the cylinder and the work done by the gas during this process. 150 N =95 kPa -3.2kg 35 cm² Figure A1-c

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter2: Steady Heat Conduction

Section: Chapter Questions

Problem 2.39P: The tip of a soldering iron consists of a 0.6-cm- diameter copper rod, 7.6 cm long. If the tip must...

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