University Physics with Modern Physics (14th Edition)

Published by Pearson
ISBN 10: 0321973615
ISBN 13: 978-0-32197-361-0

Chapter 19 - The First Law of Thermodynamics - Problems - Exercises - Page 643: 19.49

Answer

See explanation.

Work Step by Step

(a) As the wind move fast, there is no heat exchange, which is expected to be in adiabatic process. According to the First Law of Thermodynamics, $ΔU = Q - W$ and when $Q = 0, ΔU = -W$. This means the work is done on the wind, hence the temperature will increase besides the internal energy. (b) For adiabatic process, $𝑇_1 𝑉_1^{𝛾−1}= 𝑇_2 𝑉_2^{𝛾−1}$ $𝑇_1^\gamma 𝑉_1^ {1-\gamma}= 𝑇_2^\gamma 𝑉_2^{1- 𝛾}$ Now we want to find the final temprerature, $T_2$ $T_2 = T_1 \frac{p_1}{p_2}^{(\gamma - 1)/ \gamma}$ $T_2 = (258 15 K) (\frac{8.12 \times 10^4 Pa}{5.60 \times 10^4 Pa})^{(1.4 - 1)/1.4} $ $T_2 = (258 15 K) (\frac{8.12 \times 10^4 Pa}{5.60 \times 10^4 Pa})^{(2/7)} $ $T_2 = 287.1 K = 13.95 ^o C$ The increase of temperature is $\Delta T = T_2 - T$ $\Delta T =13.95 ^o C - 2.0 ^o C$ $\Delta T = 11.95 ^oC$
Update this answer!

You can help us out by revising, improving and updating this answer.

Update this answer

After you claim an answer you’ll have 24 hours to send in a draft. An editor will review the submission and either publish your submission or provide feedback.