Contradiction on electric field ?

AI Thread Summary
The discussion centers on confusion regarding the equation E(t) = kq(t) and its implications for electric fields. The user questions whether a constant current would cause the electric field to increase indefinitely. Responses clarify that the definition of current was misapplied, as the scenario described involves an unphysical situation of increasing charge at a point. It is emphasized that while an infinite increase in charge would theoretically lead to an infinite electric field, this is not a realistic representation of current. The conversation highlights the importance of correctly understanding the relationship between charge, current, and electric fields.
amrice
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Hello, I'm have just started on this subject, and I am confused with the following equation:

since E(t) = kq(t)

=> \frac{dE}{dt} = k \frac{dq}{dt} = k*I

=> E = \int(kIdt)

so if there is a constant current, wouldn't my electric field blow up??

Thanks!
 
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Hi amrice, welcome to PF
amrice said:
E(t) = kq(t)
What is this equation? I have never seen it before.
 
Hmmm, it seems that you have defined current improperly. The situation you described is if you had a point charge somewhere in space at t=0, you'd have some electric field from that point charge. Your dq/dt is equivalent to somehow magically increasing the charge of that point charge, which is unphysical and not current. But yes, if you could magically increase the charge indefinitely, the electric field would blow up at t=infinity.
 
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