4. A parallel plate capacitor consists of two plates, each of area 0.02 mʻ, separated by a distance 0.001 m. The capacitor is initially charged to a potential difference of 4000 V which decreases to 1500 V when a slab
of dielectric is inserted to fill the gap between the plates.
Calculate
a) The original capacitance and the charge on each plate
[6]
b) The capacitance after insertion of the dielectric.
[3]
c) The dielectric constant.
[2]