Lift

[Multiple correct answers] A ping pong ball is rotating in a clockwise direction while translating from right to left. Choose the correct statements.

• The velocity is reinforced on the top of the ball and reduced at the bottom side.

• The velocity is reinforced on the bottom side of the ball and reduced at the top.

• The stagnation points move towards the bottom of the ball.

• The stagnation points move towards the top of the ball.

The lift due to the rotation of a body is known as the __________ effect?

Which of the following statements correctly describes the lift coefficient equation shown?

• The equation is true for airfoil with finite length and large angle of attack.

• The equation is true for airfoil with finite length and small angle of attack.

• The equation is true for airfoil with infinite length and small angle of attack.

• The equation is true for airfoil with infinite length and large angle of attack.

Planform area of the wing equals to the

• Wing span × chord length

• Wing span × wing thickness

• Chord length × wing thickness

• Cross-sectional area of the wing

What does airfoil stall mean?

• The airfoil experiences a sudden increase in acceleration

• The airfoil experiences a sudden decrease in acceleration

• The airfoil experiences a sudden increase in lift

• The airfoil experiences a sudden loss of lift

The following statements are correct except

• Wing tip vortices increases the effective angle.

• Wing tip vortices creates a downwash.

• Wing tip vortices leads to an induced drag.

• Wing tip vortices results in a smaller effective lift.

Based on the figure shown, which type of wing design is preferable?

• Smaller wing span, larger chord length

• Smaller wing span, smaller chord length

• Larger wing span, smaller chord length

• Larger wing span, larger chord length