A single moving charge constituite a current

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A single moving charge can indeed constitute a current, even if it is not steady. To have a non-zero current, the rate of change of charge (dq/dt) must be non-zero. When a charge moves, it creates a current density proportional to its charge distribution and velocity. In a wire, what we perceive as a steady current is actually the combined effect of many moving charges, creating overlapping fields. Thus, a point charge in motion behaves similarly to a continuous charge distribution, contributing to the current at that specific location.
Kolahal Bhattacharya
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Can you tell whether a single moving charge constituite a current?Not necessarily steady current.I will be happy I we get a non-steady current.To have a non-zero current we need dq/dt not equal to zero.So at point in space,we measure dq/dt and it is 0 at time t,q at time t' and 0 again at time t".So at that point the current is q/(t"-t).Please justify...
 
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Well, think about it. Let's say we have a line of charge, and start running parallel to it with a velocity v. Then suddenly it's a current with a distribution equal to the charge distribution times v. Why shouldn't this apply to a point charge?
 
ofcourse,now I can understand this.Thank you
 
A single point charge moving does indeed constitute a current at that point in space. When we speak of a current in a wire, what we mean is the aggregate effect of every moving charge in that wire. What appears to us as a steady current is in fact the overlapping fields of an enormous number of charges passing us rapidly and giving the effect of a moving charge equally at every point in space.
 
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