1- During the take-off phase of the flight of an aeroplane, drag acting on theaeroplane is mainly because of:i)Friction drag.i)Pressure drag.i)Formation of the boundary layer.iv)Tip vortices.2- Which of the following statements is true?i)The drag of a streamlined object is always less than that of an equivalentblunt object.ii)The drag of a streamlined object is always more than that of an equivalentblunt object.ii)The drag of a streamlined object is more than that of an equivalentblunt object at high Reynolds numbers.The drag of a streamlined object is more than that of an equivalentiv)blunt object at low Reynolds numbers.3- The transition of the laminar flows over wing of civilian aeroplanes can bedelayed by:i) Applying adverse pressure gradient.i) Moving the poiht of the maximum thickness towards the leading edge.i) Heating up the flow.iv) Moving the point of the maximum thickness towards the trailing edge.4- Which of the following statements is true?i) Turbulent boundary layers are susceptible to separation.ii) Flow separation decreases the form drag.iii) Reattachment of the boundary layer over the wing enhances the lift.iv) Increase in lift decreases the drag.

1- During the take-off phase of the flight of an aeroplane, drag acting on the aeroplane is mainly because of: i) Friction drag. i) Pressure drag. 间) Tip vortices. Formation of the boundary layer. iv) 2- Which of the following statements is true? i) The drag of a streamlined object is always less than that of an equivalent blunt object. i) The drag of a streamlined object is always more than that of an equivalent blunt object. i) The drag of a streamlined object is more than that of an equivalent blunt object at high Reynolds numbers. iv) The drag of a streamlined object is more than that of an equivalent blunt object at low Reynolds numbers. 3- The transition of the laminar flows over wing of civilian aeroplanes can be delayed by: i) Applying adverse pressure gradient. i) Moving the poiht of the maximum thickness towards the leading edge. ii) Heating up the flow. iv) Moving the point of the maximum thickness towards the trailing edge.

1- During the take-off phase of the flight of an aeroplane, drag acting on the aeroplane is mainly because of: i) Friction drag. i) Pressure drag. 间) Tip vortices. Formation of the boundary layer. iv) 2- Which of the following statements is true? i) The drag of a streamlined object is always less than that of an equivalent blunt object. i) The drag of a streamlined object is always more than that of an equivalent blunt object. i) The drag of a streamlined object is more than that of an equivalent blunt object at high Reynolds numbers. iv) The drag of a streamlined object is more than that of an equivalent blunt object at low Reynolds numbers. 3- The transition of the laminar flows over wing of civilian aeroplanes can be delayed by: i) Applying adverse pressure gradient. i) Moving the poiht of the maximum thickness towards the leading edge. ii) Heating up the flow. iv) Moving the point of the maximum thickness towards the trailing edge.

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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