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The term "velocity lag" refers to a
- speed error.
- acceleration error.
- position error.
Please write your question here.
How would you work out the work done by a machine assuming it is 100% efficient?
- Velocity ratio and efficiency.
- Mechanical advantage and output.
- Mechanical advantage and input.
WHY?
What is the SI units for specific heat capacity?
- Jkg-1k-1.
- Jkg-1S-1.
- Jm-1k-1.
WHY?
If a light is beamed at a flat mirror, what is the angle it reflects at?
- Angle of reflection.
- Angle of incidence.
- Angle of refraction.
WHY??
What is 1 btu/lb in j oules per kilogram?
- 2326 j/kg.
- 4128 j/kg.
- 1055 j/kg.
WHY
One degree increment on the Centigrade scale is equal to what increment on the Fahrenheit scale?
- 1.8 degrees F.
- 33 degrees F.
- 12 degrees F.
THIS IS WRONG.
C=5/9(F-32)
THEN IT IS 33C
1 kW is
- 3413 BTU per hour.
- 1.56 HP or 1100 W.
- 4200 BTU per hour.
WHY???
One atmosphere is equal to
- 10.3 lbf/in2.
- 14.7 lbf/in2.
- 29.92 in. Hg.
WHY????
What frequency is a tone which is 4 times the fundamental frequency?
- 2nd overtone.
- 3rd overtone.
- 3rd harmonic.
WHY????
What is the current through resistor C?
- 4.5A
- 18A
- 9A
Someone can explain please?
Atmospheric pressure at ISA conditions is
- 1013 pa.
- 1013bar.
- 1013mBar
explain
A gauge indicates 15 PSIG. What is the absolute pressure?
- 30 PSI.
- 15 PSI.
- 45 PSI.
why?
A gauge indicates 15 PSIG. What is the absolute pressure?
- 30 PSI.
- 15 PSI.
- 45 PSI.
Please write your question here.
A gyro with a fixed point free to rotate in three axis is
- a tied gyro.
- a free gyro.
- a rate gyro.
why?
A gyro with a fixed point free to rotate in three axis is
- a tied gyro.
- a free gyro.
- a rate gyro.
Please write your question here.
Compared with the flap up configuration the maximum angle of attack for the flaps down configuration is
- unchanged.
- larger.
- smaller.
in Cl/aoa graphics, flaps-down line remains upwards parallel. so, why the answer is not unchanged?
The purpose of the rotating guide vanes on a centrifugal compressor is to
- direct the air smoothly into the impeller.
- provide initial diffusing of the air.
- prevent damage by solid objects.
can someone please explain to me?
Acoustic linings made from composite materials are used in what section of the engine?
- Not used to suppress noise.
- Hot section and Cold Section.
- Cold section only.
i dont understand
For fire detection and extinguishing purposes, aircraft powerplant areas are divided into fire zones based on
- the volume and smoothness of the airflow through engine compartments.
- engine type and size.
- hot and cold sections of the engine.
i think this asnwer is also wrong my pdf says "The zoning layout will depend on the characteristics of the
individual engin"
Following the reports of a heavy landing you would
- carry out a complete visual examination of the power plant.
- examine the engine mountings and borescope the nozzle guide vanes and turbine.
- examine the engine mountings and fuse pins.
why not the mountings?
Screech liners in the afterburning jet pipe
- prevent unstable combustion.
- prevent cyclic vibrations of large amplitude.
- acts as noise suppressors.
i think the answer is wrong my textbook says that they act as noise suppressors.I quote "These are commonly called as Noise suppression liners or Noise
attenuation mattresses. When installed in the exhaust area these
are also known as Screech liners"
What happens to air flowing at the speed of sound when it enters a converging duct?
- Velocity increases, pressure and density decreases.
- Velocity, pressure and density increase.
- Velocity decreases, pressure and density increase.
Why?
If you have an aircraft that is more laterally stable then directionally stable it will tend to
- bank.
- slip.
- skid.
Why?
What type of intake is one that decreases gradually in area and then increases?
- Convergent.
- Convergent / Divergent.
- Divergent.
isnt this divergent only?Why can it be also convergent?I think convergent is the opposite of what it says.
Water methanol for cooling is injected into the
- compressor inlet or outlet.
- engine hot zone.
- combustion chamber.
why isnt methanol injected into combustion to help with the freezing of water?