A roller coaster has a mass of 275 kg. It sits at the top of a hill with height 85 m. If it drops from this hill, how fast is it going when it reaches the bottom?

1 Answer
Nov 9, 2016

Answer:

#sf(41color(white)(x)"m/s")#

Explanation:

The potential energy of the roller coaster is converted into kinetic energy when it reaches the bottom.

So we can write:

#sf(cancel(m)gh=1/2cancel(m)v^(2))#

#:.##sf(v=sqrt(2gh))#

#sf(v=sqrt(2xx9.8xx85)=41color(white)(x)"m/s")#

As you can see, the mass given is irrelevant to the question.