Help!!! (1 Viewer)

[T_Brendan_T]

Does anyone know how to do this question

 

[T_Brendan_T]

Does anyone have a solution to this

 

[jimmysmith560]

Would the following working help?

Firstly, determine the weight force,





As the plane is moving with an acceleration, there must be a resultant force.

This can be found using the following formula:






The thrust is in the direction of travel, that is, down at 8° to the horizontal.

The lift force must balance the weight, and is perpendicular to the airflow.

The drag opposes the motion in the direction of the airflow.

From this information, you can construct the force polygon as shown:



(This is analogous to the normal reaction and the friction force in friction problems).

From the diagram, the drag force is scaled off at 73.1 kN.

The lift force is scaled off at 34.7 kN

Therefore, the L/D ratio is 34.7 / 73.1 = 0.47

 

[T_Brendan_T]

Thank you a lot