Simple conceptual reference frame question

AI Thread Summary
When a train decelerates while a bed remains stationary on top, the bed appears to accelerate in the opposite direction due to the train's change in velocity. This phenomenon is explained by the concept of frames of reference, where the bed's motion is observed relative to the decelerating train. The deceleration of the train is typically measured against an inertial frame, such as the track, while the bed's apparent acceleration is relative to the accelerating train. Understanding this requires clarifying the reference points for both the train's deceleration and the bed's acceleration. This discussion highlights the importance of defining frames of reference in physics to grasp motion dynamics accurately.
Rubberduck2005
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Homework Statement
If a train is moving at some constant V with a bed sitting still on top. When the train decelerates at some rate -A then the bed will move at some acceleration A. I can't seem to get an intuition for how this comes to be. I have looked online and find no help.
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If a train is moving at some constant V with a bed sitting still on top. When the train decelerates at some rate -A then the bed will move at some acceleration A. I can't seem to get an intuition for how this comes to be. I have looked online and find no help.
 
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Seems pretty straightforward.

If you're sitting on top of the train, what do you see the (wheeled) bed do ?
 
Rubberduck2005 said:
If a train is moving at some constant V with a bed sitting still on top. When the train decelerates at some rate -A then the bed will move at some acceleration A.
One assumes that you are learning about "frames of reference".

When you say that the train is decelerating, you should further qualify that statement. What is that deceleration relative to? Probably you mean that the deceleration is relative to an inertial frame in which the track is at rest.

When you say that the bed is accelerating, you should further qualify that statement. What is that acceleration relative to? Probably you mean that the deceleration is relative to an accelerating frame of reference in which the train is at rest.

The bed seems to be accelerating because the coordinate system you are measuring its acceleration against is itself accelerating.
 
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