an airplane rolls down the runaway. compared to which reference point is the airplane in motion?
In this scenario, the reference point for determining the motion of the airplane would typically be the ground or the Earth's surface. This is because the airplane is moving in relation to the stationary surface of the Earth.
To understand the motion of the airplane, you can visualize a situation where you are observing the airplane from a fixed position on the ground. As the airplane rolls down the runway, you can notice its movement relative to the ground. This perception of the airplane's motion is based on the reference point of the unmoving Earth.
It's important to note that the choice of reference point can sometimes vary depending on the context or the problem being analyzed. However, in most cases involving the motion of an airplane on a runway, the Earth's surface is the typical reference point.