Explain the concept of a parallel plate capacitor. State its any 'two' applications.
Open in App
Verified by Toppr
The surface of an isolated charge conductor is an equipotential surface with a potential V with respect to some arbitrary zero reference level, usually the ground. V>0 if charge on the conductor is positive and V<0 for negative charge. If the charge is increased. V increases in the same proportion. i.e.
C is called the capacitance.
Consider a metal plate A whose potential is raised to V by depositing a charge +Q on it. Now if an uncharged metal plate B is brought close to A A, then the negative charge will be induced on the surface near A and positive free change on the surface of B away from A as know below.
Now if plate B is grounded, the free positive charge on B will go into the earth. The bound negative charge (−Q) on B will lower the potential of A by say V1 due to the presence of plate A in the electric field generated by the negative charge on B.
Now net potential on A=V−V1
As (V−V1) has decreased from V the capacity or capacitance of plate A has increased.
This system of plates together is called a parallel plate capacitor.
Application of parallel plate capacitors:-
1) Energy storage capacitor banks are used for power factor correction with inductive loads
2) DC power supplies sometimes use parallel capacitors in order to better filter the output signal and eliminate the AC ripple.
Solve any question of Electrostatic Potential and Capacitance with:-