Using Impulse-Momentum to Find Time of Falling Object

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The discussion focuses on applying the impulse-momentum theorem to determine the time it takes for a falling object to accelerate from a speed of 5.50 m/s to 9.00 m/s. The user initially calculated a time of 3.5 seconds but later corrected their approach. Using the formula vf = vi + at and substituting the values, they found the correct time to be approximately 0.357 seconds. The calculations involved understanding momentum and impulse, emphasizing the relationship between force, mass, and acceleration due to gravity. The thread concludes with a successful resolution of the problem.
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Homework Statement


Use the impulse-momentum theorem to find how long a falling object takes to increase its speed from 5.50 to 9.00 .


Homework Equations


deltaP = impulse
P = momentum (m*v)
impulse = J (integral from ti to tf)

The Attempt at a Solution


3.5 seconds, though, I knew before that it was incorrect.
 
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well, I got it, now :)
vf = vi + at
-9 = -5.5 -9.8t
solve for t = .357 seconds
 

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