Solve My Train Dilemma: Can I Jump High Enough?

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Discussion Overview

The discussion revolves around the physics of jumping inside a high-speed train and the implications of different frames of reference on the jump's outcome. Participants explore concepts related to motion, reference frames, and the effects of atmospheric conditions on jumping behavior.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • Some participants assert that if one jumps inside a moving train, they will land back in the same spot due to Newton's laws, assuming they remain within the train's frame of reference.
  • Others argue that once free from the train's confines, the rules governing motion relative to the train no longer apply, suggesting that one might land in a different position.
  • A participant emphasizes that a frame of reference is not a physical entity but rather a coordinate system that can be defined for analysis.
  • Another participant clarifies that all objects exist in all frames of reference simultaneously, and the choice of frame is arbitrary and based on convenience for analysis.
  • Some participants discuss the example of a bus to illustrate how different frames of reference can lead to different interpretations of motion, highlighting the importance of context in understanding motion.
  • Concerns are raised about the clarity of the term "frame of reference" and its application in the discussion, with some suggesting it has led to confusion.
  • One participant notes that jumping vertically out of the train would result in being affected by atmospheric drag, causing one to land towards the back of the train.

Areas of Agreement / Disagreement

Participants express differing views on the implications of jumping in a moving train and the nature of frames of reference. There is no consensus on whether one would land in the same spot or elsewhere after jumping, and the discussion remains unresolved regarding the interpretation of frames of reference.

Contextual Notes

Limitations include potential misunderstandings of the concept of frames of reference and the effects of atmospheric conditions on motion. The discussion also reflects varying levels of familiarity with physics concepts among participants.

Einstein60
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Assuming I'm in a train moving at a very high speed. According to Newton if I jump up, I must land at the same place. But what if I had the aptitude/ability to jump very very high, will I be moving in the air and land at the same place.
 
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I think up till when we are confined with in the train as a frame of reference this will apply but when we become free from the bounding of this frame of reference no longer we will be the Rule(bounding) of this frame will apply
So I think we will jump back at some places other then from which we previously jumped from
 
Zeeshan Ahmad said:
I think up till when we are confined with in the train as a frame of reference this will apply but when we become free from the bounding of this frame of reference no longer we will be the Rule(bounding) of this frame will apply
So I think we will jump back at some places other then from which we previously jumped from
Please I don't
Understand
 
Einstein60 said:
Assuming I'm in a train moving at a very high speed. According to Newton if I jump up, I must land at the same place. But what if I had the aptitude/ability to jump very very high, will I be moving in the air and land at the same place.
Why would you not land in the same place ?
 
Zeeshan Ahmad said:
I think up till when we are confined with in the train as a frame of reference this will apply but when we become free from the bounding of this frame of reference no longer we will be the Rule(bounding) of this frame will apply
This is not correct. A frame of reference is not a tangible physical thing. At the level of sophistication of first year physics, a frame of reference can be thought of as a coordinate system (*). It is something that you conjure up with a pencil and paper. Thus it can have no physical effects whatsoever.

For an object to be "in" a frame of reference only means that it has coordinates relative to that frame.

(*) More technically, a frame of reference in first year physics stops a bit short of being a full blown coordinate system. It only establishes a standard of rest. One can then pick an origin and lay down a coordinate system (Cartesian, polar or whatever) using that standard of rest.
 
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jbriggs444 said:
This is not correct. A frame of reference is not a tangible physical thing. At the level of sophistication of first year
Here frame of reference to my understanding is the object or thing to which comparative we are considering the motion
It is just only not a pancel drawing

Same in first year physics their is given the example of a bus which is moving we you present inside with one frame of reference we are in motion (surrounding of the bus) and other we are at rest (set or passenger in the bus)
 
Zeeshan Ahmad said:
Here frame of reference to my understanding is the object or thing to which comparative we are considering the motion
It is just only not a pancel drawing.
Not so. All objects are in all frames of reference at all times.

Which one we use is a free choice. We can make that choice after the fact, when we put pencil to paper and begin analyzing the scenario. In the case at hand, we can consider our man jumping on the train from a frame of reference anchored to the tracks, from a frame of reference anchored to the train or from a frame of reference anchored to a vulture circling overhead.

It is convenient to adopt a frame of reference anchored to the train since the intent of the question is that "in the same place" means "in the same place relative to the train".
 
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Zeeshan Ahmad said:
Same in first year physics their is given the example of a bus which is moving we you present inside with one frame of reference we are in motion (surrounding of the bus) and other we are at rest (set or passenger in the bus)
This is often sloppily presented as "the people in the bus are in frame A and the people outside are in frame B", but that is wrong. The correct statements would be "the people in the bus are at rest in frame A and the people outside are moving in frame A", and "the people in the bus are moving in frame B and the people outside are at rest in frame B". As @jbriggs444 says, everything is in all frames and nobody is obligated to use their rest frame (for example, if you are on the bus you will ask "when do we arrive at my stop", tacitly adopting a frame where the bus is moving, and not "when does my stop arrive at the bus").
 
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Ok thank for guidance
Ibix said:
This is often sloppily presented as "the people in the bus are in frame A and the people outside are in frame B", but that is wrong. The correct statements would be "the people in the bus are at rest in frame A and the people outside are moving in frame A", and "the people in the bus are moving in frame B and the people outside are at rest in frame B". As @jbriggs444 says, everything is in all frames and nobody is obligated to use their rest frame (for example, if you are on the bus you will ask "when do we arrive at my stop", tacitly adopting a frame where the bus is moving, and not "when doe
 
  • #10
Einstein60 said:
Assuming I'm in a train moving at a very high speed. According to Newton if I jump up, I must land at the same place. But what if I had the aptitude/ability to jump very very high, will I be moving in the air and land at the same place.
Inside the train, the atmosphere is moving with the train. You will return to the same place you jumped from if you stay inside the train. You remained inside the train FoR.

If you jump vertically out of the train, into the apparent headwind of the atmosphere, you will be accelerated backwards by atmospheric drag, and so land towards the back of the train.
You have three FoR, the train, the atmosphere, then the train again. You will fall over backwards when you land because you are traveling backwards relative to the faster train.
 
  • #11
Baluncore said:
If you jump vertically out of the train, into the apparent headwind of the atmosphere, you will be accelerated backwards by atmospheric drag, and so land towards the back of the train.
You have three FoR, the train, the atmosphere, then the train again. You will fall over backwards when you land because you are traveling backwards relative to the faster train
Yes to the same context I have explained but the term (frame of reference) have taken the the discussion out of context
 
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