Why direct current is called direct current?

Answer 1

Because of the chemicals and metals which are used to make it, a battery can only produce dc (direct current).

For the same reason a battery cannot produce ac (alternating current) on its own, but it can be connected to another device, which is called an invertor, to produce ac for use by devices which require ac instead of dc.

Many of the devices and other pieces of equipment to which a battery can be connected will only work on direct current (such as, for example, car starter motors) but some things (such as light bulbs) can work on either dc or ac.

Some batteries are rechargeable but they cannot be recharged using ac . That is why all battery chargers which are designed to plug into house ac power sockets must convert the ac to dc.

For more information please see the answers to the Related Questions shown below.

Answer 2

The term DC or direct current is really a little misleading, However DC refers to the potential difference in an electrical charge from positive + to negative -. In the case of direct current the current is constantly from positive to negative or in one direction so to speak. In the case of an alternating current the current is constantly changing direction from positive to negative to positive to negative and so forth.

Answer 3

Direct current is called so because it flows in one direction through a circuit, without changing direction periodically. This is in contrast to alternating current, which reverses direction periodically.