08 May 2011

What is a rheostat?

CBSE PHYSICS

What is a rheostat?

A rheostat is a resistor with variable resistance.There are many type of rheostat,involved of a rotary-type rheostat and a sliding rheostst.I dunn know much about the rotary-type rheostat but I can tell u how does a sliding rheostat work.


A sliding rheostst consists of a coil resistance wire wound on a tube and a sliding contact.The sliding contact be moved on the metal bar.Consider of the length of the resistance wire which let electric current through increases,the reistance would be higher and decrease the elctric current.Thus by moving the sliding contact,we can adjust the size of electric current.It's ofter used as a dimmer or to adjustl the voluime of the radio.
If you are interested in the rotary-type rheostat,try to find it by yourself!

Question: What is the purpose of rheostate?

A rheostat is essentially a variable resistor. It is used in circuits to drop voltage or limit current.

Who invented Rheostat? 
charles wheatstone


1 comment:

  1. a rotary rheostat functions almost identical to a sliding rheostat. the only difference is that the wiper (contact point) moves in a circular instead of linear way.

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