Nonconservative Forces Problem with a Model Airplane

[momoneedsphysicshelp]

Homework Statement

A model plane of mass 5.3 kg moves from a height of 15 m to a height of 17 m while decreasing its speed from 14 m/s to 8 m/s. How much work is done by non-conservative forces acting on the plane?

Relevant Equations

—350 J
+104 J
—88 J
—245.9 J
+350 J
—104 J
+88 J
+245.9J
—15.9 J
+15.9 J

I am sure that the answer will be negative, but I'm not 100% sure on how to solve the problem. My initial answer was -350 J. Please help. Thanks!

 

[haruspex]

Homework Statement:: A model plane of mass 5.3 kg moves from a height of 15 m to a height of 17 m while decreasing its speed from 14 m/s to 8 m/s. How much work is done by non-conservative forces acting on the plane?
Relevant Equations:: —350 J
+104 J
—88 J
—245.9 J
+350 J
—104 J
+88 J
+245.9J
—15.9 J
+15.9 J

My initial answer was -350 J.

I assume those "Relevant Equations" are the options.
(That section of the template is for standard physics equations, like F=ma.)
Please post your working.

 

[Lnewqban]

Homework Statement:: A model plane of mass 5.3 kg moves from a height of 15 m to a height of 17 m while decreasing its speed from 14 m/s to 8 m/s. How much work is done by non-conservative forces acting on the plane?
... I am sure that the answer will be negative, but I'm not 100% sure on how to solve the problem. My initial answer was -350 J. Please help. Thanks!

This problem seems to be confusing to me, unless we assume that the model airplane does not have a thrust force acting on it.
A powerful engine would constantly supply mechanical energy to the airplane, which would need to be accounted for in the solution of the problem.
Let's assume the model is a glider instead.

If so, it is not different from a problem showing a ball rolling on an inclined plane and increasing is height respect to the ground.
Initial kinetic energy is used to increase potential energy and to overcome frictionor aerodynamic drag in the case of the airplane.

https://www.grc.nasa.gov/www/k-12/airplane/smotion.html

 

[hutchphd]

This problem seems to be confusing to me, unless we assume that the model airplane does not have a thrust force acting on it.

The thrust, if present, will be one of the nonconservative forces ! If you are confused, why try to answer the question?

For the OP consider conservation of energy. Show how you got your answer (I'm not going to do it as per our suggested rules)