What Is the Total Energy in an Oscillating LC Circuit?

In summary, in an oscillating LC circuit with L=25 mH and C=7.8 x10^-6 F, and initial values of current at 9.2 mA and charge on capacitor at 3.8 x 10^-6 C, the total energy in the circuit can be calculated using the formula Ub+Ue=U. L and C are constant for these types of questions and are not affected by the initial conditions.
  • #1
spottedcow913
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In an oscillating LC circuit, L=25 mH and C=7.8 x10^-6 F. At time t=0 the current is 9.2 mA, the charge on the capacitor is 3.8 x 10^-6 C, and the capacitor is charging. What is the total energy in the circuit?

I know I just need to do Ub+Ue=U, but here is my question. Are L and C constant for these types of questions? Because my initial thought is that I can't use L and C because it doesn't say they are at t=0 like the other values.
 
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  • #2
Yes, L and C are constant. They depend on the physical properties of the circuit devices themselves.
 

Related to What Is the Total Energy in an Oscillating LC Circuit?

1. What is total energy in an LC circuit?

The total energy in an LC circuit refers to the combined energy stored in both the inductor and capacitor of the circuit. It is the sum of the magnetic energy stored in the inductor and the electric energy stored in the capacitor.

2. How is the total energy in an LC circuit calculated?

The total energy in an LC circuit can be calculated using the formula E = 1/2 * L * I^2, where E is the total energy, L is the inductance of the inductor, and I is the current flowing through the circuit. Alternatively, it can also be calculated using the formula E = 1/2 * C * V^2, where C is the capacitance of the capacitor and V is the voltage across the capacitor.

3. Why is the total energy in an LC circuit constant?

In an LC circuit, the energy is constantly being transferred back and forth between the inductor and the capacitor. This means that the total energy remains constant because the energy stored in one component is equal to the energy stored in the other component at any given time.

4. What happens to the total energy in an LC circuit over time?

In an ideal LC circuit, the total energy remains constant over time. However, in real-world circuits, there may be some energy loss due to resistance, which can cause the total energy to decrease gradually over time.

5. How does the total energy in an LC circuit affect the oscillations?

The total energy in an LC circuit determines the amplitude of the oscillations. As the energy is transferred back and forth between the inductor and capacitor, the amplitude of the oscillations will decrease gradually due to energy losses. When the total energy is depleted, the oscillations will stop completely.

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