Finding uniformly increasing acceleration.

AI Thread Summary
To find the acceleration of a rocket that travels 650 meters in 12 seconds from rest, the relevant equation is s = v_i * t + (1/2) * a * t^2. Plugging in the known values, the correct approach leads to the calculation of acceleration as 9 m/s². The attempt to use the change in velocity equation was unnecessary, as the initial velocity is zero and the change in velocity is not needed for this problem. The first equation alone suffices to solve for acceleration. Thus, the solution demonstrates that understanding the appropriate equations is crucial in physics problems.
AcousticBruce
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Homework Statement



What is the acceleration of a rocket that travels uniformly from rest and travels 650m in the first 12 seconds.

Homework Equations



s=v_it+\frac{1}{2}at^2

a=\frac{\Delta v}{\Delta t}

The Attempt at a Solution



I pluged the acceleration equation into the first equation.

s=0(12)+\frac{1}{2}\frac{650}{12}12^2

that equaled 7800 m/s squared. That is so far off. The answer is 9 m/s squared.
 
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You don't need the second equation, and it's not useful because you don't know what the change in v was.

The first equation is perfectly adequate. You know s, you know vi and you know t. Solve for a.
 
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