As discussed earlier, the charging of a capacitor is the process of storing energy in the form electrostatic charge in the dielectric medium of the capacitor. Consider an uncharged capacitor having a capacitance of C farad. This capacitor is connected to a dc voltage source of V volts through a resistor R and a switch S as shown in Figure-1.
The other factor which affects the rate of charge is the capacitance of the capacitor. A higher capacitance means that more charge can be stored, it will take longer for all this charge to flow to the capacitor. The time constant is the time it takes for the charge on a capacitor to decrease to (about 37%).
C = Q/V, Q = CV, V = Q/C Thus charge of a capacitor is directly proportional to its capacitance value and the potential difference between the plates of a capacitor.Charge is measured in coulombs. One coulomb of charge on a capacitor can be defined as one farad of capacitance between two conductors which operate with a voltage of one volt.
The capacitance C of a capacitor is defined as the ratio of the maximum charge Q that can be stored in a capacitor to the applied voltage V across its plates. In other words, capacitance is the largest amount of charge per volt that can be stored on the device: C = Q V
Consider a circuit having a capacitance C and a resistance R which are joined in series with a battery of emf ε through a Morse key K, as shown in the figure. When the key is pressed, the capacitor begins to store charge. If at any time during charging, I is the current through the circuit and Q is the charge on the capacitor, then
A higher capacitance means that more charge can be stored, it will take longer for all this charge to flow to the capacitor. The time constant is the time it takes for the charge on a capacitor to decrease to (about 37%). The two factors which affect the rate at which charge flows are resistance and capacitance.