Basic Physics (2) Flashcards
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. Constant force of 70 pounds is required to move the loaded hoist. What is the total work input required to move the hoist?
a. 840 foot pounds
b. 1,890 foot pounds
c. 1,050 foot pound
a. 840 foot pounds
The speed of sound in the atmosphere
a. Varies according to the frequency of the
sound
b. Changes with a change in temperature
c. Changes with a change in pressure
b. Changes with a change in temperature
The purpose of aircraft wing dihedral is to
a. Increase lateral stability
b. Increase longitudinal stability
c. Increase lift coefficient of the wing
a. Increase lateral stability
What is absolute humidity?
a. The temperature to which humid air must be
cooled at constant pressure to become
statured.
b. The actual amount of the water vapor in a
mixture of air and water.
c. 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.
b. 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?
a. Sound frequency (cps)
b. Ambient temperature
c. Barometric pressure
b. Ambient temperature
The desire effect of using winglets on an aircraft’s
wingtips is to
a. Increase the lift to drag ratio
b. B. reduce the aspect ratio
c. Optimize wing dihedral and improve lateral
stability
a. Increase the lift to drag ratio
If the fluid pressure is 800 psi in a ½ inch line supplying an actuating cylinder with a piston area of 10 square inches, the force exerted on the piston will
be
a. 4000 pounds
b. 8000 pounds
c. 800 pounds
b. 8000 pounds
Temperature is a measure of the potential. If both the volume and the absolute temperature of a confined gas are doubled, the pressure will
a. Not change
b. Be halved
c. Become four times as great
a. Not change
The purpose of stall strips on airplane wings is to
a. Increase lift in the areas of installation
b. Prevent stall in the areas of installation
c. Ensure that the wing root areas stall first
c. Ensure that the wing root areas stall first
A wing with very high aspect ratio (in comparison with low aspect ratio wing) will have.
a. Increased drag at high angles of attack
b. A low stall speed
c. Poor control qualities at low airspeeds
b. A low stall speed
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.
a. 120 pounds of force
b. 360 foot-pounds
c. 40 foot-pounds
b. 360 foot-pounds
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
a. 40 pounds
b. 120 pounds
c. 360 pounds
a. 40 pounds
The temperature to which humid air must be cooled at constant pressure to become saturated is called
a. Dew point
b. Absolute humidity
c. Relative humidity
a. Dew point
If the object is weighed 60 pounds. The amount of force applied to rope A to lift the weight is
a. 32 pounds
b. 15 pounds
c. 16 pounds
b. 15 pounds
In physics, which of the following factors are necessary to determine power?
- Force exerted
- Distance moved.
- Time required
Ans. 1,2 and 3
