The dielectric strength of air at $NTP$ is $3 \times {10^6}\,V/m$ then the maximum charge that can be given to a spherical conductor of radius $3\, m$ is
A$3 \times {10^{ - 4}}\,C$
B$3 \times {10^{ - 3}}\,C$
C$3 \times {10^{ - 2}}\,C$
D$3 \times {10^{ - 1}}\,C$
Medium
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B$3 \times {10^{ - 3}}\,C$
b (b) By using $E = 9 \times {10^9} \times \frac{Q}{{{R^2}}}$
$==>$ $3 \times {10^6} = 9 \times {10^9} \times \frac{Q}{{{{(3)}^2}}}$ $==>$ $Q = 3 \times {10^{ - 3}}\,C$
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