Question

A 240 kg roller coaster car Rolls over the crest of the roller coaster with a speed of 2.2m/s.if it falls through a vertical height of 12m down the tracks to the bottom of a trough, how fast will it be travelling?

So here's what I did but I don't think it's right:

Eg=mgh
=240x9.8x12
=28224J

Ek=(1/2)(240)(2.2)
=264J

EM=ek+eg
=28488

So I assumed that h=0 at the bottom of the trough

Eg=9.8x0x240
=0

So therefore ek=28489

28488J=1/2(240)v^2
15.4m/s=v

I'm not sure if this is actually correct?? Thank you so much

Answer 1

looks actually correct to me

Answer 2

“Ek=(1/2)(240)(2.2)
=264J”

This is wrong. Ek = 1/2mv SQUARED. Not 1/2mv.