In a car engine operating at 1.80 × 10³ rev/min, the expansion of hot, high pressure gas in a cylinder against a piston occurs on a timescale of 10 ms. In contrast, energy transfer by heat takes minutes or hours. (a) Can we safely assume that virtually no heat energy leaves the hot gas during expansion? Which one of the four thermal processes can we use as an approximation for this situation? (b) Assume the cylinder contains 0.100 moles of an ideal monatomic gas that goes from 1.20 × 10³ K to 4.00 x 10² K during the expansion. Calculate the work done by the gas on the piston.

In a car engine operating at 1.80 × 10³ rev/min, the expansion of hot, high pressure gas in a cylinder against a piston occurs on a timescale of 10 ms. In contrast, energy transfer by heat takes minutes or hours. (a) Can we safely assume that virtually no heat energy leaves the hot gas during expansion? Which one of the four thermal processes can we use as an approximation for this situation? (b) Assume the cylinder contains 0.100 moles of an ideal monatomic gas that goes from 1.20 × 10³ K to 4.00 x 10² K during the expansion. Calculate the work done by the gas on the piston.

University Physics Volume 2

18th Edition

ISBN:9781938168161

Author:OpenStax

Publisher:OpenStax

Chapter3: The First Law Of Thermodynamics

Section: Chapter Questions

Problem 56P: Consider a cylinder with a movable piston containing n moles of an ideal gas. The entire apparatus...

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