A parallel plate air capacitor of capacitance 245 pF has a charge of magnitude 0.148 μC on each plate. The plates are 0.328 mm apart then the potential difference between the plates would beChoose answer: 604 V 620 V 600 V 588 V

The potential difference across the plates of a capacitor is 200 V and the charge stored is 4 µC. The capacitance is:a) 20 µFb) 2 µFc) 0.02 µFd) 0.2 µF

A parallel plate capacitor with a capacitance of 2 µF is connected to a 100 V battery. If the separation between the plates is doubled, the capacitance is:a) 1 µFb) 4 µFc) 0.5 µFd) 2 µF

n air gapped parallel plate capacitor has plate separation 0.01 m.(a) (2 marks) The capacitor is charged to 50 V, and remains connectedto the voltage source so that voltage remains at 50 V as a dielectricwith r = 3.4 is inserted so that it completely fills the gap between theplates. Find the magnitudes of the E-field, D-field, and P-field. Ignoreany possible fringing effects.(b) (2 marks) Start again with the capacitor discharged and air gapped.The capacitor is charged to 50 V, but this time the terminals discon-nected, leaving it charged. After the dielectric is inserted, find themagnitudes of the P-field, E-field, and D-field, and the new voltagebetween the plates. Ignore any possible fringing effects

Calculate capacitance of each capacitor if equivalent capacitance of the combination is 4 pF.(ii) Calculate the potential difference between the plates of X and Y.(iii) Estimate the ratio of electrostatic energy stored in X and Y

n a spherical capacitor with plate radii a & b, the potential difference between the plates is V. The electric field between the plates at a radial distance r from centre isChoose answer: