Stone Falling Motion: Debunking the Myth of Upward Acceleration in Reverse

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The discussion centers on the motion of a stone falling and the implications of running a film of that motion in reverse. While the film shows the stone accelerating upwards when played backwards, the actual acceleration remains downward as the stone slows while rising. Participants clarify that reversing the film does not equate to reversing the laws of physics; it merely presents the motion in reverse without altering the underlying principles. The consensus is that the acceleration is always downward, regardless of the film's direction. The conversation highlights the distinction between visual representation and physical reality.
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A motion picture is made of a stone falling down. It shows that the acceleration is downward. Now run the film backwards. It will show the stone accelerating upwards.

True or false?

I am not sure on this one...I think it is false, because if traced backwards, the stone is actually slowing down as it is reaching the top from which it was initially thrown. :confused:

Thanks so much everyone!
 
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You are correct. What the backwards film will show is a rising stone, but the acceleration will still be downwards since it slows down as it rises.
 
If you run the film backwards, time is running backwards an dso any observations are null.
 
You're just running the movie backwards, not the universe! :smile:
 
Thanks so much!
 
Doc Al said:
You're just running the movie backwards, not the universe! :smile:

Ah i interpreted traced as something else!
 

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