In a parallel plate air capacitor of capacitance 4 F if the lower half of air space is filled with a material of dielectric constant 3, its capacitance changes to

Options

A. `4/3` F
B. `8/3` F
C. 8 F
D. 12 F

Answer

( c)

Explanation

Net capacitance ,C =`C_(1) + C_(2)` ……(1)
Capacitance of `I^(st)` half plate ,
`C_(1) = epsilon_(0)A/2 /d = epsilon_(0)A/2d = 4F/2 =2F`
Capacitance of II^(nd) half plate ,
`C_(2) = kepsilon_(0)A/2 /d`
` = (k/2 epsilon_(0)A/d) = 3/2 xx 4 = 6F`
`:. C = 2 + 6 = 8 F`