I teach 9th grade physical science, and we were doing an activity last week investigating whether GPE before an object falls = KE at the point the object hits the ground. This was a pretty crude activity involving dropping things out the window and timing with stop watches, so when the data didn’t look very good, I was not surprised. We were solving for velocity. Later, I got to wondering what the velocity should have been, so I calculated the velocity using the distance the object fell and g. Then when I calculated KE using a mass of 1 kg and PE using a weight of 9.8 N, the KE was ½ what it should have been----or the PE was twice what the KE was. I am no physicist, and I feel dazed and confused. Help please. We were dropping from ledge 6 meters off the ground.