91影视

(a)

The work is done on the wind as chinook winds descend the slope. The winds move fast here thus this process is called adiabatic process.

There is no exchange of heat in adiabatic process,

鈭哘=0

Using first law of thermodynamics,

鈭哘=鈭哢+奥

鈭�0=鈭哢+奥

鈭粹垎鲍=-奥

The internal energy increases and thus the temperature of the chinook wind rises as it descends the slopes because the work done on air is in an adiabatic process.

(b)the temperature in Denver rise

strong wind is blowing toward Denver with elevation,

H_D=1630m

H_Gp=4350m

Air pressure,

P_D=8.12脳10⁴Pa

P_Gp=5.60脳10⁴Pa

Temperature,

T_Do=2.0鈩�=275.151办

T_Gp=-15.0鈩�=258.15碍

Specific heat ratio for standard air is,

纬=1.4

In the adiabatic process,

P^1-纬T^纬=constant

PD 1-纬纬= PGp 1^-TGp

$$\begin{gathered} {\left(\frac{T_D}{T_{GP}}\right)}^Y={\left(\frac{P_{GP}}{P_D}\right)}^{1-纬} \\ {\left(\frac{T_D}{T_{GP}}\right)}^Y={\left(\frac{P_D}{P_{GP}}\right)}^{纬-1} \\ \frac{T_D}{T_{GP}}={\left(\frac{P_D}{P_{GP}}\right)}^{\frac{纬-1}{纬}} \end{gathered}$$

^{$$\begin{gathered} T_D=\left(258.15K\right)脳{\left(\frac{8.12脳{10}^{4}Pa}{5.60脳{10}^{4}Pa}\right)}^{\left(\frac{1.4-1}{1.4}\right)} \\ {T}_D=\left(258.15K\right)脳{\left(\frac{8.12脳{10}^{4}Pa}{5.60脳{10}^{4}Pa}\right)}^{\left(\frac{2}{7}\right)} \\ {T}_D=287.1K \end{gathered}$$}

The Denver鈥檚 temperature increases,

鈭唗=- T_Do

鈭唗= (13.95-2.0)鈩�

鈭唗=11.95鈩�

Thus, the temperature in Denver rises when the chinook arrives is 11.95 鈩�.