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1. The problem statement, all variables and given/known data

A small rocket is launched vertically, attaining a maximum speed at burnout of 1.0x10^2 m/s and thereafter coasting straight up to a maximum altitude of 1519 m. Assuming the rocket accelerated uniformly while the engine was on, how long did it fire and how high was it at engine cutoff? Ignore air friction

2. Relevant equations

Kinematics and Law of universal gravity equation

3. The attempt at a solution

I thought the time could be solved by using the 1st kinematics where Vf = 1.0 x 10^2m/s and Vi = 0m/s and a = 9.8m/s^2. The time I found was 10.2041s which isn't correct. Is that because gravity would change during the time the rocket reaches burnout? If so, how would I go about solving this problem.

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# Homework Help: Universal Gravitation and rockets

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