A parallel plate air capacity 'C' farad, potential 'V' volt and energy 'E' joule . When the gap between the plates is completely filled with dielectric

Options

A. both V and E increase
B. both V and E decrease
C. V decrease, E increases
D. V increases. E decrease

Answer

B

Explanation

Note we have considered that the battery is kept disconneted from the capacitor.
When a dielectric is being ntroduced inside the paralle plate capacitor, then potential difference gets reduced,
i.e, `V = (V_(0))/(k)`
The energy decreases , i.e, `U= (U_(0))/(k)`
where, K is the dielectric constant.