If a charged capacitor is kept aside then it is found that after some time its charged gets reduced or lost.
The reason behind the side effect is capacitor losses which are as fallows.
1.RESISTANCE LOSS:
There always exists some resistance in the capacitor plates, connecting leads and wires and it causes loss of electrical energy. Therefore, the loss of electrical energy caused due to resistance of the capacitor is known as resistance loss (I^2R).
2.LEAKAGE LOSS:
A minute flow of electrons from negative to positive plate of the capacitor always exists in a charged capacitor through the dielectric. The capacitor gets heated up due to this leakage. In this way, the loss of electrical energy caused due to flow of current through the dielectric of the capacitor is known as the leakage loss.
Since, no ideal insulator is available hence the leakage loss cannot be eliminated completely. Of course, the use of a dielectric having high dielectric constant can be reduces the leakage loss, e.g. ceramic.
3.DIELECTRIC LOSS:
If a charged capacitor is short-circulated with a piece of wire, it gets discharged. But, on testing the capacitor after some time a little amount of charge is found in the capacitor. The reason behind the side effect is dielectric absorption. In this way, it becomes evident that the electron orbits distributed while charging have not restored their original arrangement even after discharging the capacitor.
The aforesaid effect increases even further if A.C. applied across the capacitor and it goes on increasing with a rise in the frequency. In this way, the absorption of electrical energy by the dielectric on high frequencies is termed as dielectric loss.
The electron orbits get continually disturbed if A.C. voltage is applied across the capacitor and the loss of electrical energy occurred is termed as dielectric hysteresis loss.
The reason behind the side effect is capacitor losses which are as fallows.
1.RESISTANCE LOSS:
There always exists some resistance in the capacitor plates, connecting leads and wires and it causes loss of electrical energy. Therefore, the loss of electrical energy caused due to resistance of the capacitor is known as resistance loss (I^2R).
2.LEAKAGE LOSS:
A minute flow of electrons from negative to positive plate of the capacitor always exists in a charged capacitor through the dielectric. The capacitor gets heated up due to this leakage. In this way, the loss of electrical energy caused due to flow of current through the dielectric of the capacitor is known as the leakage loss.
Since, no ideal insulator is available hence the leakage loss cannot be eliminated completely. Of course, the use of a dielectric having high dielectric constant can be reduces the leakage loss, e.g. ceramic.
3.DIELECTRIC LOSS:
If a charged capacitor is short-circulated with a piece of wire, it gets discharged. But, on testing the capacitor after some time a little amount of charge is found in the capacitor. The reason behind the side effect is dielectric absorption. In this way, it becomes evident that the electron orbits distributed while charging have not restored their original arrangement even after discharging the capacitor.
The aforesaid effect increases even further if A.C. applied across the capacitor and it goes on increasing with a rise in the frequency. In this way, the absorption of electrical energy by the dielectric on high frequencies is termed as dielectric loss.
The electron orbits get continually disturbed if A.C. voltage is applied across the capacitor and the loss of electrical energy occurred is termed as dielectric hysteresis loss.
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