The net external force on the propeller of a 3.6 kg model airplane is 8.4 N forward.

Question

What is the acceleration of the airplane?
Answer in units of m/s
2

Answer 1

8.4 = 3.6 a
so
a = 8.4/3.6
IF the airplane is stopped and there is no drag on the airplane surfaces due to the propeller wake and there is no friction between the plane and the runway