Asked by mssailormouth

A roller coaster with people on board has a total mass of 4500 kg and starts at a height of 22 meters with a speed of 2.0 m/s. 50 kJ of work is done by friction on the way to the bottom of the ride. What is the speed at the bottom of the ride?

I'm LOST...no clue how to start exam Monday :(
Answered by bobpursley
KE at bottom=KE at top + PE at top -work done by friction
Answered by mssailormouth
I've got a huge number this cannot be right.

1/2(4500)(2.0)^2 + 4500(9.8)(22)-50000=929200?????
Answered by mssailormouth
KE bottom
KE top=PE top -friction
1/2(4500)v^2=4500(9.8)(22) -50000
v=20