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InterviewSolution
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If dielectric strength of air (minimum field required for ionisation of a medium) is `3 M V//m`, can a metal sphere of radius 1cm hold a charge of 1 coulomb ? |
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Answer» Here, `q = 1C and r = 1cm = 10^(-2) m`. Electric field intensity at the surface of the sphere, `E = (q)/(4pi in_(0) r^(2)) = (9xx10^(9)xx1)/((10^(-2))^(2))` As this value of E is much greater than the dielectric strength of air `(3 MV// = 3xx10^(6) V//m)`, therefore air around the sphere will get ionised and the entire charge from the sphere will leak out into air. Hence the sphere will leak out into air Hence the sphere of radius 1cm cannot hold 1 coulomb of charge in air. |
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