model rocket is launched straight upward with an initial speed of 50.0 m/s. It accelerates with a constant upward acceleration of 1.00 m/s2 until its engines stop at an altitude of 130 m.

(a) What is the maximum height reached by the rocket?
m

(b) How long after lift-off does the rocket reach its maximum height?
s

(c) How long is the rocket in the air?
s

3 answers

Follow the approach outlined in this similar question of a few days ago:

http://www.jiskha.com/display.cgi?id=1283656710
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