## Trending News

Promoted

# A rollercoaster is travelling at 5 m/s at point A on the diagram below. ?

A rollercoaster is travelling at 5 m/s at point A on the diagram below. How much time will it take the rollercoaster to stop between the points C and D if it slows at 3m/s2 in this part of the track? Assume no friction.

Update:

show all work

### 1 Answer

Relevance

- davidLv 71 month ago
Total energy at A = (1/2)m(5^2) + m(9.8)140

energy at C = (1/2)m(v^2) + m(9.8)80

change in energy = 0 .. conservation of energy with no friction

(1/2)m(v^2) + m(9.8)80 = (1/2)m(5^2) + m(9.8)140

.... mass will cancel

(1/2)(v^2) + (9.8)80 = (1/2)(5^2) + (9.8)140

v = 51.11 m/s

Vf = Vi + at

0 = 51.11 - 3t

t = 17.0367 sec

d = vi t - (1/2)at^2

d = 51.11(17.0367) - (3/2)(17.0367)^2 = 435.37 m

distance c-d is not great enough to get it to stop.

- Login to reply the answers

Still have questions? Get your answers by asking now.