(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A rocket is launched vertically up with no initial velocity. Propulsion is provided by the ejection of mass with constant velocity of ejection u = 66.0 m/s relative to the rocket and at a constant rate so determined that the initial acceleration is zero. The mass of fuel that can be ejected is 94.0% of the total mass at launch. Assuming constant gravitational acceleration, how long does it take the rocket to achieve maximum upward acceleration?

u=66.0 m/s

Mass of fuel that can be ejected=94.0% of total mass at launch

g=9.81

2. Relevant equations

(1) ΔP=F_{g}Δt

(2) V_{f}-V_{i}=uln(M_{i}/M_{f}

and maybe...

(3) Ru=Ma

3. The attempt at a solution

Alright, so first I found the delta t by plugging in the numbers given into (1). Then I solved for the final velocity using (2). Now I have no idea where to go and how to find the maximum acceleration and what time that happens at...just a point in the right direction would be nice!!!

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# Homework Help: Time it takes for a rocket to reach maximum acceleration

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