[Professor René Leriche honored with the American Prize]

An RLC series circuit comprises an inductor, a resistor, and a charged capacitor connected in series. When the circuit is closed, the capacitor begins to discharge through the resistor and inductor by transferring energy from the electric field to the magnetic field. Here, the resistor connected to the circuit causes energy losses; therefore, on the complete discharge of the capacitor, the magnetic field energy acquired by the inductor is less than the original electric field energy of the...

Consider an RLC series circuit consisting of a resistor, an inductor, and a capacitor connected to an AC voltage source. A current, which varies sinusoidally over time, flows through the circuit, and this can be expressed by the following equation:

Consider an AC generator with a frequency of 50 hertz and a voltage of 120 volts. The AC generator is connected to an RLC series circuit with a 20-ohms resistor, a 0.2-henry inductor, and a 0.05-farad capacitor. Determine the impedance, current amplitude, and phase difference between the generator's current and emf.
To solve the problem, first, determine the known and unknown quantities in the problem. Recalling the reactance equation for the inductor and capacitor and substituting the values,...

When current flow is opposed in a DC or AC circuit, it is referred to as resistance or impedance, respectively. Impedance plays a key role in determining the performance of AC circuits. It is represented by Z, which is a combination of resistance and reactance, and depends upon the angular frequency, measured in ohms.
Thus, the magnitude of the impedance is given by the following equation,

Street lamps equipped with RLC surge protectors are an excellent example of applying circuit analysis in practical scenarios. These surge protectors safeguard the lamp's components against sudden voltage spikes.
A simplified parallel RLC circuit model with a DC input source generating a step response is employed in this context. When the switch is turned on, Kirchhoff's current law is applied, leading to a second-order differential equation.

The direction in which the induced emf drives the current around a wire loop can be found through the negative sign. However, it is usually easier to determine this direction with Lenz's law, named in honor of its discoverer, Heinrich Lenz (1804–1865). Lenz's law states that the direction of the induced emf drives the current around a wire loop always to oppose the change in magnetic flux that causes the emf.
If a bar magnet is moved toward a coil such that the magnetic flux through the coil...