The change in internal energy U for a closed systemundergoing a thermodynamic pr

Question

The change in internal energy U for a closed systemundergoing a thermodynamic process may be approximated by therelation: U = mc(T2 - T1) Where m is the mass of the substance within the system (kg), cis the average specific heat of the substance (J/kg C), andT1 and T2 are the inifial and finaltemperatures of the substance (Centigrades) for the process. A rigid tank contains 10 kg of steam at 250 C. During thenext 5 min, the rate of heat transfer from the tank is 3 kW. What is the final temperature of the steam? For steam, let c = 1.411 kJ/kg C The change in internal energy U for a closed systemundergoing a thermodynamic process may be approximated by therelation: U = mc(T2 - T1) Where m is the mass of the substance within the system (kg), cis the average specific heat of the substance (J/kg C), andT1 and T2 are the inifial and finaltemperatures of the substance (Centigrades) for the process. A rigid tank contains 10 kg of steam at 250 C. During thenext 5 min, the rate of heat transfer from the tank is 3 kW. What is the final temperature of the steam? For steam, let c = 1.411 kJ/kg C

Explanation / Answer

Mass m = 10 kg

Initila temp T 1 = 250 oC

Time t= 5 min = 5 * 60 s = 300 s

Rate of heat transfer P = 3 kW = 3000 W

Specific heat of steam c = 1.411 kJ / kg oC = 1411 J / kgoC

Heat transfer Q = Pt = 900000 J

We know Q = mc ( T 2- T 1)

T 2- T 1 = Q / mc

               = 63.78 oC

Final temp T 2 = T 1 + 63.78

                        = 313.78 oC

Related Questions

Navigate

• Browse (All)
• Browse T
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.