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consider the flow of air through a supersonic nozzle. the reservoir pressure and temperature are 5 atm and 500 k, respectively. if the mach number at the nozzle exit is 3, calculate the exit pressure, temperature, and density.

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The exit pressure, temperature, and density are approximately 1.21 atm, 289.5 K, and 0.415 kg/m³.

Let's find the exit pressure, temperature, and density for the given flow of air through a supersonic nozzle.

We are given the following information:

Reservoir pressure (P0) = 5 atm

Reservoir temperature (T0) = 500 K

Mach number at the nozzle exit (M) = 3

where:

p is the pressure at the nozzle exit

T is the temperature at the nozzle exit

ρ is the density at the nozzle exit

γ is the specific heat ratio of air (1.4 for air)

First, we can use the first isentropic relation to solve for the exit pressure:

p/p0 = (1 + (γ - 1)M^2)^(-γ/(γ - 1))

p/5 atm = (1 + (1.4 - 1)3^2)^(-1.4/(1.4 - 1))

p/5 atm ≈ 0.242 atm

p ≈ 1.21 atm

Next, we can use the second isentropic relation to solve for the exit temperature:

T/T0 = (1 + (γ - 1)M^2)^(-1)

T/500 K = (1 + (1.4 - 1)3^2)^(-1)

T/500 K ≈ 0.579

T ≈ 289.5 K

Finally, we can use the third isentropic relation to solve for the exit density:

ρ/ρ0 = (1 + (γ - 1)M^2)^(-1/(γ - 1))

ρ/ρ0 ≈ 0.622

ρ ≈ 0.415 kg/m³ .

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