Adapters

An adapter or adaptor is a device used to match the physical or electrical characteristics of two different things so that a connection may be made between them. more...

An adapter may be very simple, connecting one kind of plug to another kind of socket, but not changing what passes through. One example would be a garden hose, which normally has threads that screw on, but can be attached to an adapter which allows it to snap easily on and off of faucets, other hoses, or attachments. Likewise, a serial port may require an adapter to connect between the old DB-25 type and the later DE-9 type, which have 25 and 9 pins (respectively) but only 9 wires each.

Other adapters may include a device that changes what is passing through, such as a transformer that adapts household electrical current from high voltage (100 to 240 volts) to low voltage (3 to 24 volts) suitable for consumer electronics.

Rocketry

The hollow cylindrical or conical segments between rocket stages or between the top rocket stage and the shroud that houses a spacecraft are called adapters. They transfer the thrust from the lowest stage and are discarded during staging. This usage, which may appear overelaborate in that such adapters are inert structural elements rather than dynamic converters of signals or electrical power, actually derives from French.

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