Throwing a ball out of the end of a moving train

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Discussion Overview

The discussion revolves around the scenario of a ball being thrown from the last cart of a moving train on the moon, specifically examining the motion of the ball as perceived by a stationary observer on the ground. The context includes considerations of relative motion in a vacuum and the implications of throwing an object at the same speed as the train's movement.

Discussion Character

  • Exploratory
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • One participant describes a scenario where a train moves at 50 mph on the moon, and a ball is thrown from the train at the same speed in the opposite direction, questioning the motion of the ball as seen by a stationary observer.
  • The same participant reiterates the scenario, emphasizing the conditions and asking for thoughts on the outcome.
  • Another participant suggests that the original poster should provide more information or demonstrate their own reasoning before seeking answers, indicating a preference for a more engaged discussion rather than direct answers.

Areas of Agreement / Disagreement

The discussion does not appear to reach a consensus, as participants express differing views on how to engage with the problem and the expectations for responses.

Contextual Notes

The scenario assumes a perfect vacuum and does not address potential complexities related to gravitational effects or the mechanics of motion in such an environment.

Who May Find This Useful

Individuals interested in physics, particularly those exploring concepts of relative motion, kinematics, and the effects of gravity in different environments.

Dnj23
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Let's say there is a train moving at 50 mph on the moon on a flat surface (say it's a perfect vacuum) and you are on the last cart where you throw a ball out the rear in the opposite direction the train is moving (directly away from it, parallel to the ground). The ball thrown is also instantaneously 50 mph. Let's also also say that there is an observer on the ground by the track not moving, and the ball was thrown just as it passed the observer.

From the ground observer, would the ball appear to not move at all in the vacuum, then fall to the ground, maybe bounce up and down a few times, but never move an inch?
 
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Dnj23 said:
Let's say there is a train moving at 50 mph on the moon on a flat surface (say it's a perfect vacuum) and you are on the last cart where you throw a ball out the rear in the opposite direction the train is moving (directly away from it, parallel to the ground). The ball thrown is also instantaneously 50 mph. Let's also also say that there is an observer on the ground by the track not moving, and the ball was thrown just as it passed the observer.

From the ground observer, would the ball appear to not move at all in the vacuum, then fall to the ground, maybe bounce up and down a few times, but never move an inch?
What do you think and why?
 
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Perhaps this can give you some insight:
 
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Motore said:
Perhaps this can give you some insight:
I see you are new to the forum, so you may not have gotten the hang of the guidelines yet but you are not supposed to spoon-feed an answer, particularly when the OP has been asked to give more information or show his own attempt at a problem, as was the case prior to your post.
 

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