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Josielle Abdilla
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in an LC circuit the current does no drop to 0 but varies sinusoidally. The capacitor is recharged with a different polarization. Why is this so?
It has to do with the way that the energy stored in the inductor and capacitor are out of phase, so when the capacitor if fully charged one way, it is storing all of the energy in the circuit and the inductor current is zero, and that voltage then causes an increasing current that discharges the capacitor to zero volts, and the inductor stores all of the energy due to the max current that is flowing. That current keeps flowing to charge the capacitor to the other polarity, and the cycle keeps repeating itself.Josielle Abdilla said:in an LC circuit the current does no drop to 0 but varies sinusoidally. The capacitor is recharged with a different polarization. Why is this so?
Merlin3189 said:https://www.physicsforums.com/attachments/259381
The same sort of thing can be done for a Spring - Mass system, where energy exchanges between PE of stretched or compressed spring and KE of mass.
All have a relationship between two stores of energy.
There's a very simple answer to this, based on logic, without Maths. The Energy has to go somewhere and the Energy in the Magnetic Field will be transferred to Energy in the Electric Field in the Capacitor. Also, there can be no instantaneous changes in any of the variables so current will keep flowing past the zero value until the Energy is all in the Capacitor (and so on. . . . .). The oscillation would go on for ever except for the necessary resistance in a real circuit and the radiation of EM waves which will always be there and there will be an exponential decay in the amplitude..Josielle Abdilla said:in an LC circuit the current does no drop to 0 but varies sinusoidally. The capacitor is recharged with a different polarization. Why is this so?
The current in an LC circuit does not drop to 0 because of the presence of inductance and capacitance. Inductance stores energy in the form of a magnetic field, while capacitance stores energy in the form of an electric field. These two components work together to keep the current flowing even when the voltage source is removed.
When the voltage source is removed from an LC circuit, the inductor releases its stored energy in the form of a magnetic field. This changing magnetic field then induces a current in the capacitor, which in turn releases its stored energy in the form of an electric field. This back-and-forth transfer of energy between the inductor and capacitor keeps the current flowing in the circuit.
Technically, yes. In an ideal LC circuit, the current will eventually decrease to 0 due to the resistance in the circuit. However, in a real-world circuit, there will always be some amount of resistance, so the current will never truly reach 0.
The fact that the current does not drop to 0 in an LC circuit is important because it allows for the continuous flow of energy in the circuit. This is useful in many applications, such as in electronic devices and power transmission systems.
Yes, the current in an LC circuit can be controlled by adjusting the values of the inductance and capacitance. By changing these values, the frequency at which the energy is transferred between the inductor and capacitor can be altered, thus affecting the current in the circuit.