Originally Posted by yodudedudeyo
in a world without air resistance, a bullet shot out of a gun and a bullet dropped from the height of the gun will reach the ground at the same time.
I think you forgot to say "shot horizontally
In both cases, the vertical velocity will be zero, and the acceleration due to gravity will be same. So they will both hit the ground at the same time.
However, if one bullet is fired at
the earth at speed X, and another just dropped at speed Y (Y < X), don't expect the 2 to magically equalize and hit the ground together.