What is Direct Current ?

When a DC is required

but motors convert electrical energy into mechanical energy (if the shaft on a motor is spun, a voltage is generated at the terminals!

This is useful for many large appliances like dishwashers, refrigerators, and so on, which run on AC.

Negative points

Direct current is a bit easier to understand than alternating current. Rather than oscillating back and forth, DC provides a constant voltage or current.

DC can be generated in a number of ways:

An AC generator equipped with a device called a “commutator” can produce direct current
Use of a device called a “rectifier” that converts AC to DC
Batteries provide DC, which is generated from a chemical reaction inside of the battery

The electrons in direct current flow in one direction. The current produced by a battery is direct current

Using our water analogy again, DC is similar to a tank of water with a hose at the end.

The tank can only push water one way: out the hose. Similar to our DC-producing battery, once the tank is empty, water no longer flows through the pipes.

The electrons in alternating current flow in one direction, then in the opposite direction—over and over again

DC is defined as the “unidirectional” flow of current; current only flows in one direction. Voltage and current can vary over time so long as the direction of flow does not change

To simplify things, we will assume that voltage is a constant. For example, we assume that a AA battery provides 1.5V, which can be described in mathematical terms as:

The current supplied to your home by the local utility is alternating current.

the use of battery is uneconomical or requires constant charging

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Almost all electronics projects and parts for sale on SparkFun run on DC. Everything that runs off of a battery, plugs in to the wall with an AC adapter, or uses a USB cable for power relies on DC. Examples of DC electronics include:

Cell phones
The LilyPad-based D&D Dice Gauntlet
Flat-screen TVs (AC goes into the TV, which is converted to DC)
Flashlights
Hybrid and electric vehicles

Almost every home and business is wired for AC. However, this was not an overnight decision. In the late 1880s, a variety of inventions across the United States and Europe

a power supply is used to convert the ac to dc.

The current flow alternates 120 times per second in the United States. In Europe it alternates 100 times per second

led to a full-scale battle between alternating current and direct current distribution.

Alternating current was chosen early in the 20th century as the North American standard

In 1886, Ganz Works, an electric company located in Budapest, electrified all of Rome with AC.

This will charge the battery, and the equipment used off the mains until the battery is depleted

Dc is our harmful