1.5 Work S.J.T.U. Phase Transformation and Applications Work a function of the path taken Case I:A Case II:B W=-(-) W=-(2-) W={PdV=(P.-PXV,-V) isobaric isobaric V V V2 Volume Volume SJTU Thermodynamics of Materials Spring 2010 ©X.J.Jin Lecture 1 First law I 21/38Phase Transformation and Applications S. J. T. U. SJTU Thermodynamics of Materials Spring 2010 © X. J. Jin Lecture 1 First law I 21/38 1.5 Work Work a function of the path taken P2 P1 V1 V2 1 2 Pressure Volume A isobaric isochoric P2 P1 V1 V2 1 2 Pressure Volume B isobaric isochoric Case I: A ( ) W  P1 V2 V1 ( ) W  P2 V2 V1 Case II: B ( )( ) W   PdV  P2  P1 V2 V1