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Question
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Solution
Variable resistors consist of a resistance track with connections at both ends and a wiper which moves along the track as you turn the spindle. The track may be made from carbon, cermet (ceramic and metal mixture), or a coil of wire (for low resistances). The track is usually rotary but straight track versions, usually called sliders, are also available.
Variable resistance is a device used to change the resistance and hence the current flowing through a circuit; without changing the voltage.
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