Direct-Current Circuits

Electromotive force (emf) is the force that causes current to flow from a higher to a lower  potential. The term "electromotive …

A resistor is an ohmic device that limits the flow of charge in a circuit. Most circuits have more than one resistor. If several resistors are connected …

Resistors are in parallel when one end of all the resistors are connected to a continuous wire of negligible resistance and the other end of all the …

Electrical devices in any circuit can be connected either by series or parallel connections. Additionally, circuits can be connected involving both of …

Gustav Kirchhoff (1824–1887) devised two rules known as Kirchhoff's rules to analyze complex circuits, which cannot be analyzed with …

Kirchhoff's rules quantify the current flowing through a circuit and the voltage variations around the loop in a circuit. Applying Kirchhoff's …

Common devices, including car instrument panels, battery chargers, and inexpensive electrical instruments, measure potential difference (voltage), …

An ammeter is a current measuring instrument. In the circuit, it is represented by the symbol A. The ammeter is placed in series with the device or …

A voltmeter is an electrical device that measures the potential difference or voltage between two points. It is connected in parallel with the circuit …

A circuit containing resistance and capacitance is called an RC circuit. A capacitor is an electrical component that stores electric charge by storing …

One of the applications of an RC circuit is the relaxation oscillator. The relaxation oscillator comprises a voltage source, a capacitor, a resistor, and …

Companies that supply power to most modern households use three conductors, typically called a three-wire line. While one is neutral, the other two are …

A conductor needs to be a component of a path that creates a closed loop or full circuit to have a continuous current flowing through it. A current starts …

Generally, a single battery is not enough to power some devices. In such cases, batteries can be combined in two ways: in series or in parallel. In …

Voltage and current measurements using a standard voltmeter and ammeter alter the circuit being measured either by drawing or resisting the current flow, …

An ohmmeter is a resistance-measuring device. It works by applying a voltage to a resistor of unknown resistance and measuring the current across the …

A relaxation oscillator is one of the applications of RC circuits. A neon lamp relaxation oscillator comprises a capacitor, a resistor, a voltage source, …

The equivalent resistance of a combination of resistors depends on their values and how they are connected. The simplest combinations of resistors are …