# LC oscillation

LC oscillations are generated when a charged capacitor is connected to non resistive component or connected to the inductor. The oscillations which are produced by LC circuit having constant amplitude and frequency.In simple way it is named as LC oscillation because L is stands for inductor and C stands for Capacitor. In this article we will discuss about LC oscillation in ideal condition in detail.

Working of RC circuit

So let us take an example when a charged capacitor is connected to a resistor it will start discharging through the resistor. In this circuit initially current flow is maximum and it will decrease with interval of time and this is occur because initially the charge difference is maximum and it will reduces with discharging of capacitor. The discharging time of capacitor is depends up on the RC time constant which is given as T=R*C. if we plot a graph between time and current it will look like spikes of a signal which is described in below picture.

Working of LC circuit

In second case we will connect a charged capacitor to an inductor in this case capacitor start its discharging through the inductor and you can see current is not increasing suddenly as we have seen in case of RC circuit. This will happen due property of inductor to opposes the change in the flow of current in circuit. So capacitor will discharge gradually through the inductor after discharging an opposite emf is produced across the inductor as you see in below picture. Opposite emf is produced as per the below formula

VL= -L di/dt

When opposite polarity emf is produced across inductor it will starts charging the capacitor with opposite polarity and forms a negative half cycle of the wave and this process will continous and produces the LC oscillations.This circuit is also termed as LC tank circuit.

Note if circuit resistance is increased it will causes energy decay in form of heat and it will affect the oscillations.

Applications of  LC circuits

LC circuits have large number of applications at high frequency ranges given as below

• Used in mobile communication.