Robert, a stuntman, projects himself from a height of 50.0 meters in a horizontal direction. He safely lands at a horizontal distance of 100.0 meters. Calculate the horizontal velocity with which Robert projected himself. A. 4.90 meters/second B. 31.30 meters/second C. 10.20 meters/second D. 12.20 meters/second

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