1. The problem statement, all variables and given/known data Calculate the change in potential energy of 2.8kg of water as it passes over Niagara falls (a distance of 50m) 2. Relevant equations U= mgh 3. The attempt at a solution I plugged in the values into the equation U=mgh= (2.8)(9.8)(50)=1372J but it was the wrong answer. I'm not exactly sure what I am doing wrong. Any help is appreciated!