Why acceleration is not 9.8m/s^2?

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The discussion centers on the average acceleration of an object dropped from a height of 39.4m, which is calculated to be 3.29×10^-2 m/s^2, rather than the expected -9.8 m/s^2. The question arises as to why the acceleration is not negative, given that it acts downwards. Possible explanations include the object not being on Earth or the influence of other forces. It is noted that the sign of acceleration is arbitrary and depends on the chosen coordinate system. Understanding these factors is crucial for correctly interpreting acceleration in physics problems.
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Homework Statement



An object is dropped from ret from a height of 39.4m. What is its average acceleration (assumed to be constant) if it hits the ground with a speed of 1.61m/s?


Homework Equations





The Attempt at a Solution



I actually got the answer from this question. But I am wondering why a is not -9.8m/s^2
The answer is 3.29×10-2 m/s^2, shouldn't it be negative as acceleration is acting downwards?
 
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Possible reasons:
- The object is not dropped on earth, but somewhere else
- Some other force acts on it

The sign of the acceleration is arbitrary and depends on the coordinate system.
 

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