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+clear;
+clc;
+disp('Example 5.22');
+
+// aim : To determine the
+// (a) new pressure of the air in the receiver
+// (b) specific enthalpy of air at 15 C
+
+// Given values
+V1 = .85;// [m^3]
+T1 = 15+273;// [K]
+P1 = 275;// pressure,[kN/m^2]
+m = 1.7;// [kg]
+cp = 1.005;// [kJ/kg*K]
+cv = .715;// [kJ/kg*K]
+
+// solution
+
+// (a)
+
+R = cp-cv;// [kJ/kg*K]
+// assuming m1 is original mass of the air, using P*V=m*R*T
+m1 = P1*V1/(R*T1);// [kg]
+m2 = m1+m;// [kg]
+// again using P*V=m*R*T
+// P2/P1=(m2*R*T2/V2)/(m1*R*T1/V1); and T1=T2,V1=V2,so
+P2 = P1*m2/m1;// [kN/m^2]
+mprintf('\n (a) The new pressure of the air in the receiver is = %f kN/m^2\n',P2);
+
+// (b)
+// for 1 kg of air, h2-h1=cp*(T1-T0)
+// and if 0 is chosen as the zero enthalpy, then
+h = cp*(T1-273);// [kJ/kg]
+mprintf('\n (b) The specific enthalpy of the air at 15 C is = %f kJ/kg\n',h);
+
+// End