Benjamin Franklin’s Fluid Theory

Benjamin Franklin imagined the electricity as a invisible fluid. Franklin assured that if any body had more fluid than usual, it could have a positive charge, but if it had less fluid than normal it had negative charge.

Current divider in parallel resistors

By using the current divider rule, we can find the current in each resistor connected in parallel. The electric current passing through a circuit of two resistors in parallel is divided in two.

What is a Voltage divider?

The Voltage divider is a circuit that allows us to obtain an output voltage less or equal to the input voltage. The output voltage is normally obtained across ground and the resistor connected to it, but it could be across any of the other resistors.

What is a wirewound resistor?

A Wirewound resistor is a resistor made with a conductive wire of a high resistivity. This wire is made of a special alloy and it is wound on a support tube of refractory material such as ceramics, porcelain, etc.

What is Direct Current? – DC

Direct Current (DC), is the result of the flow of electrons (negative charge) in a conductor (most of the time, wires of copper) that goes only in one direction.

What is Electrical Resistivity?

Electrical resistivity [ρ] (rho) is a characteristic of materials and has ohm-meter unit. Resistivity indicates how much the material opposes the flow of electric current.

Capacitor and Direct Current

If a battery is connected to a capacitor, it will allows no direct current (DC) to flow through. If a not charged capacitor is connected across the terminals of a battery, a transient current flows as the capacitor plates charge up.

Capacitor and Direct Current. Current starts from its maximum value and decreases to 0 amps. This current is called “transient current”.

Ohm’s Law explanation

You can establish a relation between the battery voltage, the resistor’s value and the electric current that passes through this resistor. This relation is: I = V/R and it is known as the Ohm’s Law.

The Superposition Theorem

The Superposition theorem states that the effect of two or more voltage sources in a resistor is equal to the sum of the individual effects of each source taken separately, replacing all the remaining voltage sources with short circuits.

What is Electrical Resistance? Obtaining a material’s resistance

The electrical resistance is a measurement of the opposition that offers a material to the passage of electrons (the electric current). When a material, such as metals has many free electrons, it allows the easy flow of electrons and it is called conductor.

Mesh analysis in a resistor network – Mesh current method in a resistor network.

Mesh current analysis or the mesh current method is a technique used to find the currents circulating around a mesh with in any closed path of a circuit.

Resistors in series and parallel How to obtain equivalent resistor value of resistors in series To implement a circuit with resistors in series you have to connect one resistor after the other one. (see the image). The equivalent resistor value of the resistors connected in series is equal to the addition of all resistor’s values. In this […]