can anyone explain how a potentiometer can be used as a variable voltage supply?

Question

anonymous · Answer

And what is a variable voltage supply circuit?

anonymous · Answer

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anonymous · Answer

We can connect potentiometer as shown across the output of a power supply with voltage Vs. Considering the terminal of the wiper arm as shown...|dw:1413875995332:dw|taking the output voltage Vo across terminals 2 and 3, the voltage across it is proportional to the resistance kR where k is the fraction of the resistance R of the whole potentiometer... this can be represented by Voltage Divider Rule such as$$V_o=kV_s$$

anonymous · Answer

A variable voltage supply circuit is a voltage supply with variable voltage output. The output voltage can be adjusted smoothly.

unklerhaukus · Answer

Turning the dial on the component, adjusts the height of the wiper arm in the diagram, and thus the resistance to the current and hence potential, at the output voltage.