A contradiction of the equivalence principle?

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Discussion Overview

The discussion centers around the equivalence principle in physics, particularly questioning whether larger masses fall towards Earth at different rates compared to smaller masses when held at the same distance. Participants explore the implications of this principle in relation to gravitational attraction and acceleration, while also addressing the role of mathematical models and experimental evidence.

Discussion Character

  • Debate/contested
  • Conceptual clarification
  • Mathematical reasoning

Main Points Raised

  • One participant questions whether larger masses should be attracted to Earth's gravity differently than smaller masses, suggesting a potential contradiction of the equivalence principle.
  • Another participant emphasizes that acceleration due to gravity is independent of mass, referencing the gravitational force equation and its implications.
  • Some participants clarify that while larger masses experience a greater gravitational force, they also possess greater inertia, leading to the conclusion that acceleration remains constant for all masses near Earth's surface.
  • A participant expresses confusion about the equivalence principle and its application, seeking clarification on whether it applies to larger scales.
  • There are discussions about the necessity of mathematical models in understanding these concepts, with some participants suggesting that avoiding equations may hinder comprehension.
  • One participant acknowledges a misunderstanding of the equivalence principle, specifically regarding the idea that all masses fall at the same velocity, and seeks confirmation of their revised understanding.

Areas of Agreement / Disagreement

Participants express differing views on the application and implications of the equivalence principle. While some clarify that acceleration due to gravity is the same for all masses, others maintain that the initial question regarding different rates of fall for larger and smaller masses remains unresolved.

Contextual Notes

Participants highlight the importance of mathematical models and experimental evidence in discussing gravitational concepts, indicating that some assumptions may be implicit in their arguments. The discussion also reflects varying levels of understanding of the equivalence principle and its implications.

  • #91
here:
E3F077FB-678F-49C1-A911-7730621462A6 (3).jpeg
 
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  • #92
DaveC426913 said:
Yes, you are correct.

You can convert F=ma to a=F/m.

For a given F: If m is small, then a is large. If m is large, then a is small.Looked at another way: Newton's first law says the F is equal and opposite, so
m1a1 = m2a2

And again, if m1 is smaller than m2, then a1 will have to be larger than a2
so sir i was right from the start i have tried to prove my point that different masses have different accelerations when dropped at same height
 
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  • #93
am i right?
 
  • #94
No. Different masses do not have different accelerations.

We have already covered this
 
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  • #95
Jeff, are you even considering the messages you are getting? You respond within seconds and we are covering the same ground over and over and over.
 
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  • #96
DaveC426913 said:
Yes, you are correct.

You can convert F=ma to a=F/m.

For a given F: If m is small, then a is large. If m is large, then a is small.Looked at another way: Newton's first law says the F is equal and opposite, so
m1a1 = m2a2

And again, if m1 is smaller than m2, then a1 will have to be larger than a2
but if this is true....
 
  • #97
disprove this i guess...
 
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  • #98
jeff einstein said:
disprove this i guess...
Sorry, we are now mixing up two things. I may be culpable for that.

Two different masses both being under the influence of the same gravity will have the same acceleration. (1)

But that's not the scenario you have diagrammed, above. The scenario you have diagrammed is about different masses under the influence of different gravity (i.e. each others'). (2)

1694713002286.png
 
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  • #99
jeff einstein said:
but if this is true....
jeff einstein said:
disprove this i guess...
You have been instructed by multiple people over multiple pages carefully explaining the situation. Carefully and repeatedly explaining where your original statements were wrong and also where they were almost right. With multiple corrections from multiple people carefully explaining the physics and the source of the confusion.

Then one single person gives one single confused answer after telling you that they were confused because of a mistaken crop, and immediately you just throw out everything you were taught by all of the previous people?

That shows that you are not seeking to learn, you are just seeking validation.

Thread closed. This topic has been done. Do not re-open, just re-read.
 
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  • #100
PeterDonis said:
The acceleration of both objects, however, is not the same, because it is the force divided by the mass of the object.

I know the topic is closed, and the OP has probably not done enough math yet to understand the full answer, but this is the so-called two-body problem:

https://en.wikipedia.org/wiki/Two-body_problem

I post it to stimulate the study of vector calculus and its applications in the future.

Way back when I studied vector calculus, this important application, interestingly, wasn't covered

Strang's calculus textbook is a good place to learn it:
https://ocw.mit.edu/ans7870/resources/Strang/Edited/Calculus/Calculus.pdf

Thanks
Bill
 
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