posted by mike .
At a playground, a 19.8 kg child plays on a slide that drops through a height of 2.13 m. The child starts at rest at the top of the slide. On the way down, the slide does a nonconservative work of -319 J on the child. What is the child's speed at the bottom of the slide?
Use conservation of energy and subtract 319 from the initial potential energy of MgH = 413 J. The difference is the kinetic energy at the bottom of the slide. Get the speed from that.