MCQ
The radius of a metallic sphere if its capacitance is $1/9\,F$, is
- A${10^6}\,m$
- B${10^7}\,m$
- ✓${10^9}\,m$
- D${10^8}\,m$
✓
Answer
Correct option: C.
${10^9}\,m$
c
(c) $C = 4\pi {\varepsilon _0}R$, $R = \frac{C}{{4\pi {\varepsilon _0}}}$ $==>$ $R = (1/9) \times 9 \times {10^9} = {10^9}\,m$
(c) $C = 4\pi {\varepsilon _0}R$, $R = \frac{C}{{4\pi {\varepsilon _0}}}$ $==>$ $R = (1/9) \times 9 \times {10^9} = {10^9}\,m$
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