1. An aluminum rod 15 cm long with a diameter of 1.0 cm is fixed between rigid supports with an Invar rod of the same dimensions such that there is no tension or compression of the rod at 20°C. The rods are attached to each other such that they can push or pull without separating. Invar has a negligibly small thermal expansion coefficient. You place this apparatus in an experiment where heat is added or removed and you measure that the Invar rod is a total of 0.25 mm longer than it was at 20°C. 2.7g/cm³, CAL = 0.90Jg-¹K-1, Data: aA = 23 x 10-6K-1, YAL YInvar = 140G Pa Aluminum 15cm Invar 15cm = 69GPa, PAL = a) Find the final temperature. b) If the particular Aluminum alloy used has a Yield strength of 200MPa, is the rod likely to be permanently deformed? c) Was heat added or removed from the Aluminum rod? How much? Clearly state all of the assumptions that you made while solving this problem.

1. An aluminum rod 15 cm long with a diameter of 1.0 cm is fixed between rigid supports with an Invar rod of the same dimensions such that there is no tension or compression of the rod at 20°C. The rods are attached to each other such that they can push or pull without separating. Invar has a negligibly small thermal expansion coefficient. You place this apparatus in an experiment where heat is added or removed and you measure that the Invar rod is a total of 0.25 mm longer than it was at 20°C. 2.7g/cm³, CAL = 0.90Jg-¹K-1, Data: aA = 23 x 10-6K-1, YAL YInvar = 140G Pa Aluminum 15cm Invar 15cm = 69GPa, PAL = a) Find the final temperature. b) If the particular Aluminum alloy used has a Yield strength of 200MPa, is the rod likely to be permanently deformed? c) Was heat added or removed from the Aluminum rod? How much? Clearly state all of the assumptions that you made while solving this problem.

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.

Chapter5: Analysis Of Convection Heat Transfer

Section: Chapter Questions

Problem 5.36P

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1.1 On a cold winter day, the outer surface of a 0.2-m-thick concrete wall of a warehouse is exposed to temperature of –5°C, while the inner surface is kept at 20°C. The thermal conductivity of the concrete is 1.2 W/m K. Determine the heat loss through the wall, which is 10-m long and 3-m high. Problem 1.1
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