Question

At a playground, a 18.7 kg child plays on a slide that drops through a height of 2.07 m. The child starts at rest at the top of the slide. On the way down, the slide does a nonconservative work of -318 J on the child. What is the child's speed at the bottom of the slide?

I have used v = sgrt 2gh and 1/2mv2 but to no avail.

Answer 1

PE at top-workdone=1/2 mv^2

Answer 2

I'm still confused. How does that equal 1/2mv2 and how does that solve the problem.

Answer 3

Starting potential energy less the work done on the way down equals the final kinetic energy.

From the final kinetic energy, you can compute the final velocity.

Answer 4

thank you, I got it