Ring Topology

In a ring topology each device has a dedicated point to point line configuration only with the two devices on either side of it. A signal trevels in one direction fron device to device untill it reaches the destination. Each device have a repeater which is used to boost the signal.

Advantages:


1. Easy installation and reconfiguration.
2. Easy to remove a device by removing two cables.
3. Fault locatingand isolation is easy.

Disadvantages:


1. Unidirectional traffic can be a disadvantage.
2. The break in the ring dtops all the communication of network.

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Inductors

Inductors store energy in a magnetic field. The magnetic field is created by passing current through a coil of wire, as is done in an electromagnet such as those used to lift scrap iron.
In electric circuits inductors often play the role of smoothing devices that reduces current variations.But when the current is forced to change abruptly, the inductor generates a large induced voltage- - large enough to cause a spark in the extreme case of an automobile ignition circuit.
This two terminal device consists of a wire coil wound around a core.The core may be cylindrical or it may be doughnut-shaped. The coil has N turns , insulated from one another and from the core.When the wire carries the current i, a magnetic field is created in the space around the coil and becomes concentrated within the core.Like an electric field, the magnetic field holds energy that comes from the source that established the field.hence,

An inductor stores energy in a magnetic field produced by current through a wire coil.The strength of the field expressed in terms of magnetic flux through the core.The proportionality constant L is the inductance which is measured in henrys (H).

V=L* di/dt Read More!