Question

Three plates `A,B` and `C` each of area `0.1m^(2)` are separated by `0.885 mm` from each other as shown in the figure. A `10 V` battery is used to charge the system. The enegry stored in the system is

A. `1 muJ`
B. `10^(-1)muJ`
C. `10^(-2)muJ`
D. `10^(-3)muJ`

Answer 1

Correct Answer - B
`C_(eq) = 2C`
`= 2xx (in_(0)A)/(d)`
`= 2xx (8.85xx 10^(-12)xx10^(-1))/(8.85xx10^(-4))`
`C_(eq) = 2xx10^(-9) F`
`U = (1)/(2)xxC_(eq) xxV^(2) = (1)/(2)xx 2xx10^(-9) xx (10)^(2) = 10^(-7)J`
`=10^(-7)muJ`