Question

The two plates of a parallel plate capacitor are 4mm apart.A slab of dielectric constant 3 and thickness 3mm is introduced between the plates with its faces parallel to them.the distance between the plates is so adjusted that the capacitance of the capacitor becomes 2/3rd of its original value.what is the new distance between the plates?

Answer 1

Answer:

6mm. C=kA/d, K is the dielectric constant, A area &d is the distance between the plates. So C becomes 2/3rd means d becomes 3/2 times, other parameters being unchanged. So 4*3/2=6mm