Question
Explain linear density, surface density and volume density for continuous charge distribution.
✓
Answer
(1) Linear distribution of electric charge.
►If there is a continuous electric charge on a line, it is called linear distribution of electric charge.
►The electric charge per unit length on an electrically charged line is called linear density of electric charge.
►Assume there is a total charge of Q on the line length of $l$.
►Linear density of charge,
$\lambda=\frac{\text { Total electric charge }}{\text { length }}=\frac{ Q }{l}$
SI unit of linear density is $C / m$
(2) Surface distribution of charge :
If there is a continuous electric charge on a surface, it is called surface distribution of charge.
►The electric charge per unit surface is called surface density of charge.
►Assume there is a total charge of Q on the Surface of Area A,
$\therefore$ Surface density of charge,
$\sigma=\frac{\text { Total electric ch arge }}{\text { Area }}=\frac{ Q }{ A }$
►SI unit : $C / m ^2$
(3) Volume distribution of charge :
If there is a continuous electric charge on a volume, it is called volume distribution of charge.
►The electric charge per unit volume is called volume density of charge.
►Assume there is a total charge Q on the matter with volume V ,
$\therefore$ Volume density of charge
$\Omega=\frac{\text { Total ch arg } e }{\text { volume }}=\frac{ Q }{ V }$
►SI unit : C $/ m ^3$
►If there is a continuous electric charge on a line, it is called linear distribution of electric charge.
►The electric charge per unit length on an electrically charged line is called linear density of electric charge.
►Assume there is a total charge of Q on the line length of $l$.
►Linear density of charge,
$\lambda=\frac{\text { Total electric charge }}{\text { length }}=\frac{ Q }{l}$
SI unit of linear density is $C / m$
(2) Surface distribution of charge :
If there is a continuous electric charge on a surface, it is called surface distribution of charge.
►The electric charge per unit surface is called surface density of charge.
►Assume there is a total charge of Q on the Surface of Area A,
$\therefore$ Surface density of charge,
$\sigma=\frac{\text { Total electric ch arge }}{\text { Area }}=\frac{ Q }{ A }$
►SI unit : $C / m ^2$
(3) Volume distribution of charge :
If there is a continuous electric charge on a volume, it is called volume distribution of charge.
►The electric charge per unit volume is called volume density of charge.
►Assume there is a total charge Q on the matter with volume V ,
$\therefore$ Volume density of charge
$\Omega=\frac{\text { Total ch arg } e }{\text { volume }}=\frac{ Q }{ V }$
►SI unit : C $/ m ^3$
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