Calculating Position of a Falling Sandbag - Hot Air Balloon Physics Question

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A hot air balloonist releases a sandbag at 40m above the ground while rising at 5m/s. After 0.250 seconds of free fall, the computed position of the sandbag is approximately 40.9m, which raises questions about its height relative to the release point. The upward initial velocity of 5m/s contributes to the sandbag's position, causing it to rise slightly before beginning its descent. Clarification is sought on the interpretation of the computed height and the importance of showing work in calculations. Understanding the initial velocity is crucial for accurate position calculations after the release.
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a hot air balloonist, rising vertically with a constant velocity of magnitude 5m/s releases a sandbag at an instant when the balloon is 40m above the ground. after it is released, the sandbag is in free fall.

a) compute position at .250s

i solved it and got ~ 40.9m, which is correct. but why is it +.9m above when it was dropped when the position of the balloonist was 40m? shouldn't it be -.9m?

is it b/c even though the sandbag was dropped at the instant the balloonist was at 40m, the position increased due to the velocity which includes a rise in position within that .250s that they were asking for?
 
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rocophysics said:
a hot air balloonist, rising vertically with a constant velocity of magnitude 5m/s releases a sandbag at an instant when the balloon is 40m above the ground. after it is released, the sandbag is in free fall.

a) compute position

i solved it and got ~ 40.9m, which is correct. but why is it +.9m above when it was dropped when the position of the balloonist was 40m? shouldn't it be -.9m?

do i have to take into consideration that the balloonist is already moving at an initial velocity of 5m/s and where the sandbag was really dropped, was above 40m?

To one part of your questions, the answer is: yes, you have to take the initial velocity of the sandbag as 5 m/sec upward because it was moving with the balloon just before it was released.

As for part (a), *what* is it you are asked to compute the position of? You should show some of your work, because I am mystified as to what 40.9 meters represents...
 
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