更多"[单选题]The coefficient of lift is a w"的相关试题:
[单选题]In general, extending large angle simple flaps increases lift and drag coefficient, decreases critical angle of attack, and _______ the ratio of lift and drag.
A.increases
B.does not change
C.decreases
D.is hard to determine whether increasing or decreasing
[单选题]Lift is proportional to the square of the airplane’s velocity. If an airplane’s speed is doubled, lift increases _______ .
A.two-fold
B.three-fold
C.four-fold
D.eight-fold
[单选题]Lift is proportional to the square of the airplane’s velocity. If an airplane’s speed is reduced by one half, lift _______ .
A.is doubled
B.increases four fold
C.is decreased to one half of the previous value
D.is decreased to one quarter of the previous value
[单项选择]The quality of college education should be measured not only by the graduate's competence but also by his commitment(信奉).（）
A. evaluated
B. observed
C. explored
D. standardized
[单项选择]The third category relates to private ______, where an equality of bargaining power is usually to be presumed.
A. stimulation
B. transactions
C. transition
D. solutions
[单项选择]From the passage we know that the security measures taken by Metro are ______.
A. in the wake of the Madrid bomb blasts
B. not visible to the passengers or passers-by
C. extensive in its coverage of public areas
D. various ranging from the use of dogs to the access to FBI
[单项选择]What does a sundial measure according to the' passage
A. It measures the length of a day and a night.
B. It measures the movement of the sun each day.
C. It measures the passing of hours, minutes and perhaps seconds.
D. It measures the shadow of the stick across the flat surface of the sundial.
[单项选择]It seems that one good measure to prevent future shock is for people to ______.
A. cherish more hope for the future
B. replace conventional ideas with modern ones
C. try to understand what is happening and prepare for the changes
D. take a closer look at how people in other cultures behave
[单项选择]A) ride C) lift
B) help D) rise
A. ride
B. help
C. lift
D. rise
[单选题]“measure”的中文意思( )
A.措施
B.可测量的
C.无限的
D.重大的
[单选题]Flaps increase lift by _______ .
A.increasing the wing’s effective camber
B.changing the chord line
C.increasing the area of the wing
D.all the above
[单选题]“take the necessary measure”的中文意思( )
A.采取行动
B.做了测量
C.做了详细的测量
D.采取必要的措施
[单项选择]It was such little boys that can't lift up ______ box.
A. so heavy a
B. so a heavy
C. such heavy a
D. a heavy such
[单选题]The primary source of lift is _______ .
A.the pressure differential created by movement of air about the wing
B.the atmospheric pressure around the airplane
C.the direction and speed of the wind around the airplane
D.the way the wings are attached to the fuselage
[单选题]_______ is the main source of lift.
A.The difference in pressure between the upper and lower surfaces of the wing
B.The difference in curvature between the upper and lower surfaces of the wing
C.The curvature on the upper portion of the wing
D.The curvature on the lower portion of the wing
[判断题] “measure”的中文意思是“措施 ” ( )
A.正确
B.错误
[单选题]In general, the direction of lift is _______ .
A.upward perpendicular to the ground
B.perpendicular to the chord line of the airfoil
C.upward perpendicular to the longitudinal axis
D.perpendicular relative to air flow
[单选题]The two primary ways to control lift are changing _______ .
A.angle of attack
B.angle of incidence
C.airspeed
D.either A or C
