49. You have been hired to design a spring launched roller coaster that will carry two passengers per car. Te car goes up a 10m high hill, then descends 15m to the track's lowest point. You've determined that the spring can be compressed a maximum of 2.0 m and that a loaded car will have a maximum mass of 400 kg. For safety reasons, the spring constant should be 10% larger than the minimum needed for the car to just make it over the top.(adsbygoogle = window.adsbygoogle || []).push({});

a. What spring constant should you specify?

b. What is the maximum speed of a 350 kg car if the spring is compressed the full amount?

I'm having trouble with part a. Here's what I've got so far:

known:

m=400kg

y0= 5m

y1= 15m

y2= 0m

v1= 0 m/s

s0= -2.0m (compression of spring)

s1= 0m

to find:

k

v0

.5mv0^2+mgy0+.5kS0^2 = .5mv1^2+mgy1+.5kS1^2

200v0^2+19600-2k = 58800

am I on the right track? how do I find out what I need to get to solve for part a of the problem?

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# Homework Help: Spring-launched rollercoaster problem

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