One mole of an ideal gas is heated at constant pressure. If an 100 Joule heat energy supplied to the gas, then work done by the gas will be …….. (gamma=1.4)

One mole of an ideal gas is heated at constant pressure. If an 100 Jou

1.	One mole of an ideal gas is heated at constant pressure. If an 100 Joule heat energy supplied to the gas, then work done by the gas will be …….. (gamma=1.4)
Answer» 28.57 J 56.54 J 38.92 J 65.38 J Solution :At CONSTANT PRESSURE `DELTAQ=nC_P DeltaT` and `DeltaU=nC_V DeltaT` From first law of thermodynamics , `DeltaW=DeltaQ-DeltaU` `=nC_P DeltaT - nC_V DeltaT` `=nDeltaT (C_P-C_V)` `THEREFORE (DeltaW)/(DeltaQ)=(nDeltaT (C_P-C_V))/(nC_P DeltaT)` `=(C_P-C_V)/C_P =1-C_V/C_P` `=1-1/gamma` `=1-1/1.4` `=0.4/1.4` `DeltaW=2/7xxDeltaQ` `therefore DeltaW=2/7xx100=200/7` `therefore DeltaW`-28.57 J