Question

Why are vertical and horizontal motion considered independent?

Answer 1

when you make components of any vector, it will have zero as the answer.

Explanation :- let's suppose there's a vector A' along x-axis. Now, lets see the effect of this vector on y and z-axis.

For this we have to make component.

Angle between x and y(or z) is 90°.

So, component of the vector along y(or z) will be A cos 90° = A × 0 = zero.