Question

An airplane flies horizontally at constant speed in a straight­line direction. Its state of motion is unchanging. In other words, it is in equilibrium. Two horizontal forces act on the plane. One is the thrust of the propeller that pulls it forward. The other is the force of air resistance (air friction) that acts in the opposite direction. Which force is greater?

Answer 1

Answer:

sum of all forces on the air plane must be ZERO

So both forces must be of same magnitude

Explanation:

As we know that airplane is moving with uniform speed is horizontal plane is a straight line

so the motion of the air plane is uniform without any acceleration

So we will have

$a = 0$

acceleration must be zero

now by Newton's law

$F_{net} = 0$

$F_1 + F_2 = 0$

so sum of all forces on the air plane must be ZERO