(a) Explanation Write the expression for the mass of water. m w = ρ w ν (I) Here, density of water is ρ w and volume is ν . Write the expression for work done by the paddle wheel. W P W i n = W ˙ P W i n Δ t (II) Here, power developed by the paddle wheel is W ˙ P W i n and change in time is Δ t . Express the energy balance by taking the entire contents of the tank, water and iron block as the system. E in − E out = Δ E system W P W i n = Δ U i r o n + Δ U i w a t e r W P W i n = [ m Fe c p , Fe ( T 2 − T 1 , Fe ) ] + [ m w c p , w ( T 2 − T 1 , w ) ] (II) Here, the total energy entering the system is E in , the total energy leaving the system is E out , the change in the total energy of the system is Δ E system , net internal energy is Δ U , paddle wheel power is W ˙ P W i n , net internal energy of iron and water is Δ U Fe and Δ U w respectively, mass of iron and water is m Fe and m w respectively, specific heat at constant pressure for iron and water is c p , Fe and c p , w respectively, final and initial temperature for iron and water is T 2 , T 1 , Cu and T 1 , w respectively. Conclusion: From the Table A-3, “properties of common liquids, solids, and foods”, Obtain the density and specific heat ( c p ) of water as 997 kg / m 3 and 4.18 kJ / kg ⋅ ° C respectively. From the Table A-3, “properties of common liquids, solids, and foods”, Obtain the specific heat ( c p ) of iron as 0 (b) To determine The exergy destroyed during the process.

8th Edition

ISBN: 8220102809444

Author: CENGEL

Publisher: YUZU

See similar textbooks

Concept explainers

Work and Heat Transfer

It is generally related to thermal engineering which tells about the use, creation, conversion and transfer of heat energy between the systems. It is also considered that to transfer heat from one source to another, transfer of masses is also required. T…

Videos

Question

Chapter 8.8, Problem 42P

(a)

To determine

The mass of the iron block

(b)

To determine

The exergy destroyed during the process.

Expert Solution & Answer

Want to see the full answer?

Check out a sample textbook solution

See solution

Chapter 8.8, Problem 41P

Chapter 8.8, Problem 43P

Students have asked these similar questions

3. Water enters the constant 125-mm inside-diameter tubes of a boiler at 7.5 MPa and 60°C and leaves the tubes at 6 MPa and 500°C with a velocity of 75 m/s. Calculate the velocity of the water at the tube inlet and the inlet volume flow rate.

2. A piston-cylinder device contains 2.4 kg of nitrogen initially at 120 kPa and 27°C. The nitrogen is now compressed slowly in a polytropic process during which PV1.3 = constant until the volume is reduced by one-half. Determine the work done and the heat transfer for this process.

1. 1.25 m³ of saturated liquid water at 225°C is expanded isothermally in a closed system until its quality is 75 percent. Determine the total work produced by this expansion, in kJ.

Chapter 8 Solutions

EBK THERMODYNAMICS: AN ENGINEERING APPR

Ch. 8.8 - What final state will maximize the work output of...Ch. 8.8 - Is the exergy of a system different in different...Ch. 8.8 - How does useful work differ from actual work? For...Ch. 8.8 - Prob. 4P Ch. 8.8 - Consider two geothermal wells whose energy...Ch. 8.8 - Consider two systems that are at the same pressure...Ch. 8.8 - Prob. 7P Ch. 8.8 - Does a power plant that has a higher thermal...Ch. 8.8 - Prob. 9P Ch. 8.8 - 8–10C Can a process for which the reversible work...

Knowledge Booster

Learn more about

Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, mechanical-engineering and related others by exploring similar questions and additional content below.