Question

Find the capacitance between the inner and outer curved cylindrical conductor surface as shown in figure :

[Space between conductor surface is filled with dielectric of K = 5.5]

• A. 6.86 PF
• B. 1.86 PF
• C. 3.26 PF
• D. 12.63 PF

Answer 1

Answer: (A)

6.86 PF

Answer 2

dC = $\frac { \varepsilon _ { 0 } \mathrm { KRd } \theta \times \mathrm { h } } { \mathrm { b } }$

All small dC are in parallel

\ C_eq = SdC = $\int _ { \theta = 0 } ^ { \frac { \pi } { 6 } } \mathrm { dC }$

= $\frac { 6 \mathrm { KhR } } { \mathrm { b } }$ $\int _ { \theta = 0 } ^ { \frac { \pi } { 6 } } d \theta$ = $\frac { \pi } { 6 }$ ×