posted by Kelly on .
Can you please show me how these answers are reached.
A fully loaded Cessna-182 airplane of mass 1290 kg has an engine failure when flying with an airspeed of 139 km/h at an altitude of 2670m on a calm day. It then glides at a constant glide angle (which is the direction of flight below the horizontal) towards a safe landing at this constant speed of 139 km/h experiencing a drag force of 1320N that opposes the direction in which the plane is moving.
Please use: g = 9.81 m s-2
(a) Find the magnitude of:
(i) The glide angle (ans 5.99 degrees)
(ii) The lift force which acts perpendicular to the wings of the plane (ans 12600 N)
(iii) The maximum distance over the ground the plane can glide while searching for a safe landing spot (ans 25500 m)
(iv) The rate with which the loaded plane is losing gravitational potential energy.(ans 51 kW)
You need to draw vectors first. I use inverse sin drag over mg to find the angle.
Then you use (mg)^2-(drag)2 for the normal force.
Use distance/tan angle to find distance.
Last one, you need to work out the y component of your vector, since m and g are constant, find y as PE = mgh and in this case h = y.