The plates of a parallel plate capacitor are charged up to `100 v`. Now, after removing the battery, a `2 mm` thick plate is inserted between the plates Then, to maintain the same potential deffernce, the distance betweem the capacitor plates is increase by `1.6 mm`. The dielectric canstant of the plate is .

Options

A. 5
B. 1.25
C. 4
D. 2.5

Answer

A

Explanation

`V=100,V, t=2mm, t(1-1/k)=1.6mm, k=?`
`t(1-1/k)=1.6`
`2[1-1/k]=1.6" "therefore K=5`