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clear;
clc;
disp('Example 5.23');
// aim : T determine the
// (a) characteristic gas constant of the gas
// (b) cp,
// (c) cv,
// (d) del_u
// (e) work transfer
// Given values
P = 1;// [bar]
T1 = 273+15;// [K]
m = .9;// [kg]
T2 = 273+250;// [K]
Q = 175;// heat transfer,[kJ]
// solution
// (a)
// using, P*V=m*R*T, given,
m_by_V = 1.875;
// hence
R = P*100/(T1*m_by_V);// [kJ/kg*K]
mprintf('\n (a) The characteristic gas constant of the gas is R = %f kJ/kg K\n',R);
// (b)
// using, Q=m*cp*(T2-T1)
cp = Q/(m*(T2-T1));// [kJ/kg K]
mprintf('\n (b) The specific heat capacity of the gas at constant pressure cp = %f kJ/kg K\n',cp);
// (c)
// we have, cp-cv=R,so
cv = cp-R;// [kJ/kg*K]
mprintf('\n (c) The specific heat capacity of the gas at constant volume cv = %f kJ/kg K\n',cv);
// (d)
del_U = m*cv*(T2-T1);// [kJ]
mprintf('\n (d) The change in internal energy is = %f kJ\n',del_U);
// (e)
// using, Q=del_U+W
W = Q-del_U;// [kJ]
mprintf('\n (e) The work transfer is W = %f kJ\n',W);
// End
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