A model rocket has a constant upward acceleration of 40.0 m/s^2 while its engine is running. The rocket is fired vertically, and the engine runs for 2.50 s before it uses up the fuel. After the engine stops, the rocket is in free fall. The motion of the rocket is purely up and down. i have two questions.(adsbygoogle = window.adsbygoogle || []).push({});

1.) What is the maximum height that the rocket reaches?

ok first i tried to find the average velocity for the up trip. 40/1.25 = 32

and after i found 32, i did 32*2.50s = 80 which is the wrong answer.

2.) What will be the speed of the rocket just before it hits the ground?

and for #2, i dont know how to start it.

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# Homework Help: Model rocket physics problem

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