g A rock is thrown downward from the top of a 38.4-m-tall tower with an initial speed of 16 m/s. Assuming negligible air resistance, what is the speed of the rock just before hitting the ground

Awater slide of length l has a vertical drop of h. abby's mass is m. an average friction force of magnitude f opposes her motion. she starts down the slide at initial speed vi. use work-energy ideas to develop an expression for her speed at the bottom of the slide. then evaluate your result using unit analysis and limiting case analysis. express your answer in terms of the variables h, m, l, vi, f and appropriate constants. vf v f