aerodynamic 1

Static pressure acts:

• only in direction of the flow
• only perpendicular to the direction of the flow
• in all directions
• only in the direction of the total pressure

Which one of the following statements about Bernoulli's theorem is correct?

• The dynamic pressure decreases as static pressure decreases
• The total pressure is zero when the velocity of the stream is zero
• The dynamic pressure increases as static pressure decreases
• The dynamic pressure is maximum in the stagnation point

In a convergent tube with an incompressible sub-sonic airflow, the following pressure changes will occur: Ps = static pressure; Pdyn = dynamic pressure; Ptot = total pressure.

• Ps increases, Pdyn decreases, Ptot remains constant
• Ps decreases, Pdyn increases, static temperature increases
• Ps decreases, Pdyn increases, Ptot remains constant
• Ps decreases, Ptot increases, static temperature decreases

Consider subsonic incompressible airflow through a venturi: I. The dynamic pressure in the undisturbed airflow is higher than in the throat; II. The total pressure in the undisturbed airflow is higher than in the throat.

• I is incorrect, II is incorrect.
• I is correct, II is incorrect.
• I is correct, II is correct.
• I is incorrect, II is correct.

The lift formula is:

• L= W
• L= CL 1/2 q V2 S
• L= n W
• L= CL 2 q V2 S

The terms 'q' and 'S' in the lift formula are:

• dynamic pressure and the area of the wing
• static pressure and dynamic pressure
• static pressure and wing surface area
• square root of surface and wing loading

An aeroplane performs a straight and level horizontal flight at the same angle of attack at two different altitudes. (all other factors of importance being constant, assume ISA conditions and no compressibility effects)

• the TAS at the higher altitude cannot be determined
• the TAS at both altitudes is the same
• the TAS at the higher altitude is lower
• the TAS at the higher altitude is higher

Total pressure is:

• measured at a small hole in a surface, parallel to the local stream
• static pressure minus the dynamic pressure
• static pressure plus the dynamic pressure
• 1/2 rho V2

What are the two main properties of air used to ascertain air density?

• Pressure and Density altitiude.
• Pressure and Temperature.
• Temperature and Pressure altitude.
• Temperature and Humidity.

When an aeroplane with the centre of gravity forward of the centre of pressure of the combined wing / fuselage is in straight and level flight, the vertical load on the tailplane will be:

• zero because in steady flight all loads are in equilibrium.
• upwards.
• downwards because it is always negative regardless of the position of the centre of gravity.
• downwards.