# A room measuring 20m x 20m x 15m is filled with air. The temperature is 22 deg C. The pressure is 1.6x10E5 N?

1:A room measuring 20m x 20m x 15m is filled with air. The temperature is 22 deg C. The pressure is 1.6x10E5 N/m2. Calculate the specific volume in the room.

2:An aircraft is flying northwest at 200 mi/hr at standard sea level conditions. Determine the air pressure far ahead of the aircraft .

3:A new experimental aircraft is flying at an altitude where the actual pressure and temperature are 4.72x10E4 N/m2 and 255.7K. Calculate the pressure altitude.

4:Given a temperature of 390R and pressure of 629.66 lb/ft2, determine the density.

5:An airfoil in a test chamber is exposed to a flow of air. Well ahead of the airfol the pressure, and density are 2116 lb/ft2 and .002377 slugs/ft3 respectively. The velocity is 100 mi/hr . At a sensor on the surface of the airfoil the pressure is measured at 2070 lb/fts. Determine the velocity at that point.

6:A missile is flying at standard sea level at a velocity of 750 mi/hr. Calculate the mach number at which it is flying.

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1:A room measuring 20m x 20m x 15m is filled with air. The temperature is 22 deg C. The pressure is 1.6x10E5 N/m2. Calculate the specific volume in the room.

TO Me, 'specific volume' means volume per mole or per mass. Check which definition your text uses.

The dimensions are a distraction and irrelevant. Just use PV = nRT ---> V/n = RT/P

2:An aircraft is flying northwest at 200 mi/hr at standard sea level conditions. Determine the air pressure far ahead of the aircraft .

ONE atmosphere

3:A new experimental aircraft is flying at an altitude where the actual pressure and temperature are 4.72x10E4 N/m2 and 255.7K. Calculate the pressure altitude.

4:Given a temperature of 390R and pressure of 629.66 lb/ft2, determine the density.

WITH WHAT GAS ? I guess air, with a nominal molar mass of 29.

density = molar mass x n /V = molar mass x P/RT

5:An airfoil in a test chamber is exposed to a flow of air. Well ahead of the airfol the pressure, and density are 2116 lb/ft2 and .002377 slugs/ft3 respectively. The velocity is 100 mi/hr . At a sensor on the surface of the airfoil the pressure is measured at 2070 lb/fts. Determine the velocity at that point.

USE Bernoulli's equation

6:A missile is flying at standard sea level at a velocity of 750 mi/hr. Calculate the mach number at which it is flying.

750/speed of sound in MPH

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• since you could directly compute the volume of the air in the room using the formula V = L x W x H, you would also need to know the density of air and then use the formula M = D x V where V is volume of air and D is density of air. however, I need to mention here that density of air is altitude-dependent, but assuming you have the room at ground level, D = 1.2 kg/m^3. hence, since V = (15 m) x (5 m) x (12 m) = 900 m^3, then: M = (900 m^3) x (1.2 kg/m^3) = 1080 kg = 1.08 x 10^3 kg, in scientific notation, of course.

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