B Confused about this force calulation in Resnick Halliday Krane Electrostatics

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The discussion centers on a confusion regarding the calculation of electrostatic force when the distance is halved and the charge changes by a factor of 1/8. Participants agree that the book's calculation is incorrect, as it fails to account for the impact of the reduced distance on the force. The correct approach should consider both the charge ratio and the distance ratio to accurately determine the resulting force. The conversation reflects a common struggle among students new to electromagnetism, emphasizing the importance of understanding these fundamental concepts. Overall, the consensus is that the book's explanation is flawed, leading to confusion in grasping the material.
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Resnick Halliday Krane Electrostatics Sample Problem 25-7 doubt
I'm confused in the calculation for R/2. The author took in account that the charge will change by a factor 1/8. But how does it show that the coloumbic force will become 1/8th. The distance will also reduce by half shouldn't that also be taken into account? Or am I missing something here?
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KnightTheConqueror said:
TL;DR Summary: Resnick Halliday Krane Electrostatics Sample Problem 25-7 doubt

I'm confused in the calculation for R/2. The author took in account that the charge will change by a factor 1/8. But how does it show that the coloumbic force will become 1/8th. The distance will also reduce by half shouldn't that also be taken into account? Or am I missing something here?View attachment 336703
Been there, done that. You are correct and the book is wrong. See discussion here.
https://www.physicsforums.com/threa...rted-on-an-electron-inside-a-nucleus.1052346/
 
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I agree with you - they've correctly calculated the charge ratio and forgotten the distance ratio.

Edit: beaten to it, I see.
 
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:welcome:
 
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KnightTheConqueror said:
Thank you, i just started electromagnetism and i got disappointed that perhaps I'm not getting proper grasp of the concepts. Thanks for clarifying the book is wrong
I wish you success with your studies. If you need more help, you know where to find it.
 
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