Afeather is dropped onto the surface of the moon. how far will the feather have fallen if it reaches the surface in 9.00 seconds?
given: g on moon = -1.63 meters/second2

   Distance of fall = (1/2) · (acceleration of gravity) · (time)²

                         =  (1/2)    ·      (1.63 m/s²)   ·   (9 sec)²

                         =          (0.815 m/s²)          ·    (81 sec²)

                         =                    66 meters  .

On Earth ... IF there were no air ... the feather would fall
397 meters in the same amount of time !