Understanding the Amplitude of Current in Halliday's Book

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Discussion Overview

The discussion revolves around the interpretation of the amplitude of current as presented in Halliday's textbook. Participants are examining the units used in the answer and questioning the absence of a time-dependent expression for current, relating it to Faraday's law of electromagnetic induction.

Discussion Character

  • Technical explanation, Conceptual clarification, Debate/contested

Main Points Raised

  • Some participants express confusion regarding the units m².T.rad/s and their relation to voltage.
  • Others note a missing 'T' (tesla) in the permeability of free space, suggesting a potential oversight in the original answer.
  • One participant questions why the current is not expressed as a function of time, referencing Faraday's formula and the relationship between flux variation and time.
  • Another participant clarifies that the answer refers to the amplitude of the electromotive force (emf), which is not time-dependent, and mentions that the formula includes the amplitude of the current, io.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the interpretation of the current's expression or the appropriateness of the units used. Multiple competing views remain regarding the relationship between amplitude, time dependence, and the application of Faraday's law.

Contextual Notes

There are unresolved questions about the assumptions underlying the use of units and the definitions of amplitude in the context of the discussion.

kent davidge
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I found this answer for an question of the Halliday's book but the units m².T.rad/s in the answer don't make sense with voltage. (sorry my poor english)
And I cannt understand why they haven't expressed the current as a function of time.

2ufcavn.jpg
 
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kent davidge said:
I found this answer for an question of the Halliday's book but the units m².rad/s in the answer don't make sense with voltage. (sorry my poor english)
And I cannt understand why they haven't expressed the current as a function of time.

2ufcavn.jpg
You have missed the T (tesla) in the permeability of free space.
 
Vagn said:
You have missed the T (tesla) in the permeability of free space.
Okay, I notice that. Can you explain me why the current was not expressed as a function of time? I learned from the Faraday's formula that the flux's variation is basically a derivative which involves the time.
 
Last edited:
Because what they wrote is the amplitude of the emf.
The amplitude is not time dependent. The formula includes the amplitude of the current, io.
 
Last edited:

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