I know I've done this problem a few times before but I'm just a fumbling idiot at the moment..(adsbygoogle = window.adsbygoogle || []).push({});

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

Rocket has an acceleration of 12m/s^2 and at an altitude of 1km the motor shuts off. What is the maximum height?

2. Relevant equations

V^2=V_i+2a(x_f-X_i)

x_f=x_i+V_i(t)+1/2at^2

3. The attempt at a solution

V^2=0+2(12)(1000)=154.92m/s

0=154.92t-9.8t^2, t=17.213s

x_f=1000+154.95(17.213)-1/2(9.8)(17.213)^2=2214.82meters

I feel like I'm doing it wrong. 12m/s^2 is the acceleration of the motor, shouldnt their be some force from gravity on the rocket while going towards 1000m?

Thanks for the help.

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# Homework Help: Simple Rocket Problem

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