Why eletric charge in Dimensional Analysis and not eletric current?

AI Thread Summary
Electric charge is considered a basic physical dimension in dimensional analysis because it represents a fundamental quantity, while electric current, defined as the flow of charge, is more complex and dependent on time. The Ampere, as an SI base unit, is influenced by relativistic effects, making charge a more stable and universal measure. The discussion also touches on the CIPM's proposal to redefine some SI base units based on fundamental constants, suggesting a shift towards more consistent and universal definitions. Many participants express that current SI definitions may require revisions to enhance clarity and coherence in scientific measurements. Overall, the preference for charge over current in dimensional analysis highlights the importance of stability and universality in physical measurements.
ksio.amaral89
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2 questions,actually:

1-Why in Dymensional Analysis is eletric charge a basic physical dimension instead of eletric current(as Ampere is a SI base unit and Coulomb isn't)?

2-I've read CIPM(or International Committee for Weights and Measures in English) is proposing new definitions for some of the current 7 base units,in which the supporters want to set some of the current definitons based on fundamental constants such as Avogadro or Planck constants.For further information:

http://www.bipm.org/cc/CIPM/Allowed/98/CIPM2009_49_TIMING_THE_NEW_SI.pdf

What's your opinion?Do you consider that the current SI definitions need revisions?
 
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As you know, current is the rate of flow of charge and therefore the unit of charge is simpler than the unit of current. Relativity has a lot to do with charge being a more convenient unit than current as charge is not affected by time dilation so the Coulomb remains the Coulomb whereas the Ampere depends on your frame of reference.
 
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