Question

an airplane has a mass of 31000 kg and takes off under the influence of a constant net force of 43500 n. what is the net force that acts on the planes 76 kg pilot

Answer 1

What's important to remember here is that the plane's net force is not going to be the same as the pilot's net force. However, they will both be undergoing the same rate of acceleration. What's also important to note is that We can use Newton's 2nd Law to pick apart this information.

We can calculate the rate of acceleration of the plane with F = ma
43,500N = 31,000kg * a
a = 1.4 m/s/s

Using this acceleration, we can find the net force on the pilot due to the plane's motion.
F = (76 kg) * (1.4m/s/s)
F = 106.65N

This is the force due to the planes acceleration in the direction opposite of the plane's motion. Because to direction is indicated, I take this to be in the negative horizontal direction.

This does not account for the gravitational force, which would just be mass * gravity directed downwards.

F_g = (76kg) * (9.8m/s/s) = 744.8 N


You can immediately see that the force of gravity is much greater than the force of the plane's acceleration. Passenger planes have a relatively low rate of acceleration on take off and need about a mile of runway to reach takeoff velocity.