PhysicsPlease help
posted by Joey on .
If I have a roller coaster, and hill 1 height is 50cm and hill height 2 is 25 cm and the PE is .9 as it approaches the top of hill 2, how do I calculate the speed.
Please help

THe PE is .9 where? Where did the coaster start?

The coaster started at .18PEthe .9 is the PE at the top of the second hill.The second hill is lower.

Well, the difference in the two Potential energies is now KEnergy, 1/2 mv^2, solve for v.

. The way to calculate this is you take the KE would be .9. You would say .9 = ½ (.035 x v^2) = 2.215. Correct or no?

Should I have done this as 1/2mv^2 = mgh
Cross out like terms and get to v^2 = square root of 2 x g x .25m(h)= 2.125 m/s
Would this be correct?