20.A 30 kg iron was put in a container with water. The water is at 10°C and the ironhas an initial temperature of 439•K until the iron was in thermal equilibrium withwater. Find the change in entropy. (Cp = 0.4 kJ/kg-K)%3D 21.A perfect gas has a value of R = 58.8 lbf-ft/lb-R and k = 1.26. If 20 Btu areadded to 5lb of this gas at constant volume when the initial temperatureis 90°F. Find T2, AH, AS, AU, and work for non - flow process.

Answered: 21.A perfect gas has a value of R =…

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter6: Forced Convection Over Exterior Surfaces

Section: Chapter Questions

Problem 6.51P

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