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What charge would be required to electri...

What charge would be required to electrify a sphere of radius 25 cm. So as to get a surfce chare density of `(3)/(pi )cm^(-3)` ?

Text Solution

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`r=25 cm =25xx10^(-2) m`
`sigma=(3)/(pi) cm^(-2)`
As, `sigma =(q)/(A)=(q)/(4 pir^(2))` [ A-surface Areaof the sphere]
`q=(4pi r^(2)) sigma`
`=4pi xx(0.25)^(2) xx(3)/(pi)`
`=0.75C`
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