Discussion
Consider a fluid flow around an airfoil as shown in figure.
The directions of drag force and lift force, respectively are along
Answer: D
Drag acts along OB and lift along OD.
By definition, drag is the component of the aerodynamic force parallel to the free-stream velocity, and lift is the component perpendicular to it. The free stream approaches at 30 degrees to the airfoil's x axis, and OB is drawn at 30 degrees to x, so OB is the free-stream direction and drag acts along it. OD is drawn at right angles to OB, so it is the lift direction.
OA and OC are the body (chord) axes. Forces along them are the axial and normal components, which coincide with drag and lift only at zero angle of attack.
No comment is present. Be the first to comment.
Loading…
Post your comment
Please log in or register to post a comment.
Examination Categories
- SSC Exams
- Banking Exams
- Teaching Exams
- Civil Services Exams
- Railways Exams
- Engineering Recruitment Exams
- Defence Exams
- State Government Exams
- Police Exams
- Insurance Exams
- Nursing Exams
- Other Government Exams
- NRA CET
- PG Entrance Exams
- Campus Placement
- MBA Entrance Exams
- CUET and UG Entrance
- Judiciary Exams
- Regulatory Body Exams
- Software Development