Why is the following situation impossible A new dieselengine that increases fuel economy

Chapter 21, Problem 30

(choose chapter or problem)

Why is the following situation impossible? A new dieselengine that increases fuel economy over previousmodels is designed. Automobiles fitted with thisdesign become incredible best sellers. Two design featuresare responsible for the increased fuel economy:(1) the engine is made entirely of aluminum to reducethe weight of the automobile, and (2) the exhaust ofthe engine is used to prewarm the air to 508C beforeit enters the cylinder to increase the final temperatureof the compressed gas. The engine has a compressionratiothat is, the ratio of the initial volume of the airto its final volume after compressionof 14.5. Thecompression process is adiabatic, and the air behavesas a diatomic ideal gas with g 5 1.40.