Question

Is projectile motion also 1d. Please give eg.

If a feather is thrown at perpedicular to the horizontal surface of moon ..will it be considered as a projectile....

Answer 1

Projectile motion is actually two dimensional, that is there could be hotizontal and vertical motions.
But there is a special case, that is, if we project something perpendicular to the surface and the force on the projectile is also perpendicular to the surface ( in this case, gravity), then the motion will be in a line or it will be one dimensional.
If we throw a feather perpendicular to the surface of moon, the gravity of moon is perpendicular to the surface and the motion will be 1 dimensional.