Physics Flashcards
Which condition is the actual amount of water vapor in a mixture of air and water?
Absolute humidity
The purpose of aircraft wing dihedral is to
Increase lateral stability
If the fluid pressure is 800 PSI in a 1/2 inch line supplying an actuating cylinder with a piston area of 10 square inches, the force exerted on the piston will be
8,000 pounds
Which will weigh the least?
35 parts of dry air and 65 parts of water vapor
If the volume of a confined gas is doubled (without the addition of more gas), the pressure will (assume the temperature remains constant)
Be reduced to one half its original value
How much work input is required to lower (not drop) a 120 pound weight from the top of a 3 foot table to the floor?
360 foot pounds
An airplane wing is designed to produce lift resulting from
Positive air pressure below the wing’s surface and negative air pressure above the wing’s surface along with the downward deflection of air.
Under which conditions will the rate of flow of a liquid through a metering orifice (or jet) be the greatest (all other factors being equal)?
Unmetered pressure, 17 PSI; metered pressure, 5 PSI; atmospheric pressure, 14.7 PSI
Which is the ratio of the water vapor actually present in the atmosphere to the amount that would be present if the air were saturated at the prevailing temperature and pressure?
Relative humidity
In physics, which of the following factors are necessary to determine power?
1) Force exerted
2) Distance moved
3) Time required
1,2, and 3
The main rotor system on a helicopter is classified in three groups. Which of these listed is NOT one of these groups?
The flexible-beam rotor system
Which of the following statements are correct?
When the collective pitch control lever is raised, the blade angle of all the rotor blades increase uniformly and they create the lift that allows the helicopter to take off vertically
(Refer to Figure 61.) The amount of force applied to rope A to lift the weight is
15 pounds
The speed of sound in the atmosphere
Changes with a change in temperature
Which of he following is NOT considered a method of heat transfer?
Diffusion
What force must be applied to roll a 120 pound barrel up an inclined plane 9 feet long to a height of 3 feet (disregard friction)? L / I = R / E
L = length of ramp, measured along the slope.
I = height of ramp
R = weight of object to be raised or lowered
E = force required to raise or lower object
40 pounds
If the temperature of a confined liquid is held constant and its pressure is tripled, the volume will
Remain the same
The desired effect of using winglets on an aircraft’s wingtips is to
Increase the lift to drag ratio
The boiling point of a given liquid varies
Directly with pressure
If all, or a significant part of a stall strip is missing on an airplane wing, a likely result will be
Asymmetrical lateral control at or near stall angles of attack.
A wing with a very high aspect ratio (in comparison with a low aspect ratio wing) will have
A low stall speed
The purpose of stall strips on airplane wings is to
Ensure that the wing root areas stall first
Which atmospheric conditions will cause the true landing speed of an aircraft to be the greatest?
High temperature with high humidity
If both the volume and the absolute temperature of a confined gas are doubled, the pressure will
Not change
An engine that weighs 350 pounds is removed from an aircraft by means of a mobile hoist. The engine is raised 3 feet above its attachment mount, and the entire assembly is then moved forward 12 feet. A constant force of 70 pounds is required to move the loaded hoist. What is the total work input required to move the hoist?
840 foot pounds
The temperature to which humid air must be called at constant pressure to become saturated is called
Dewpoint
Which statement concerning heat and/or temperature is true?
Temperature is a measure of the kinetic energy of the molecules of any substance
If a double-acting actuating cylinder in a 3,000 PSI system has a piston with a surface area of three square inches on the extension side, and a rod with cross-section area of one square inch attached to the piston on the other side, approximately how much force will the actuator be able to produce when retracting?
6,000 pounds
What is absolute humidity
The actual amount of the water vapor in a mixture of air and water
The speed of sound in the atmosphere is most affected by variations in which of the following?
1) Sound frequency (CPS)
2) Ambient temperature
3) Barometric pressure
2
Aspect ratio of a wing is defined as the ratio of the
Wing span to te main chord
Which of the following is Newton’s first law of motion generally termed the law of inertia?
Every body persists in its state of rest, or of motion in a straight line , unless acted upon by some outside force.
