Calculating Final Velocity in Free Fall from Given Displacement and Acceleration

AI Thread Summary
The discussion revolves around calculating the final velocity of riders dropped from a height of 27 meters before they begin to slow down. Using the equation vf^2 = vi^2 + 2(acceleration)(displacement), the correct final velocity before deceleration is determined to be 23 m/s. There is confusion regarding the final velocity being 0 m/s at ground level, as it is understood that the riders must reach a speed before stopping. The key point is that the final velocity refers to the speed just before deceleration starts, not at the moment they reach the ground. Understanding this distinction clarifies the calculation process.
Balsam
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Homework Statement


The Drop Zone drops riders 27m from rest before slowingthem to a stop. How fast are they moving before they start slowing down?

vf=? vi=0, di=27m[up], df=om, displacement=27m[down], acceleration=9.8m/s^2[down] Air resistance is negligable

Homework Equations


vf^2=vi^2+2(acceleration)(displacement)

The Attempt at a Solution


I already figured this out and got the right answer(23 m/s), but in this question, the final velocity isn't 0m/s. That confuses me, because the final position is when they are on the ground- shouldn't the final velocity be 0m/s.
 
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Balsam said:

Homework Statement


The Drop Zone drops riders 27m from rest before slowingthem to a stop. How fast are they moving before they start slowing down?

vf=? vi=0, di=27m[up], df=om, displacement=27m[down], acceleration=9.8m/s^2[down] Air resistance is negligable

Homework Equations


vf^2=vi^2+2(acceleration)(displacement)

The Attempt at a Solution


I already figured this out and got the right answer(23 m/s), but in this question, the final velocity isn't 0m/s. That confuses me, because the final position is when they are on the ground- shouldn't the final velocity be 0m/s.
Key word: How fast are they moving before they start slowing down? If the riders have a velocity of 0 m/s on the ground, they have come to a complete stop.
You can't move from A to B at 0 m/s.
 
SteamKing said:
Key word: How fast are they moving before they start slowing down? If the riders have a velocity of 0 m/s on the ground, they have come to a complete stop.
You can't move from A to B at 0 m/s.
That makes sense. Thank you.
 
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