Grab the "wiper" of the potentiometer (the horizontal arrow at right of resistor) and slide it up and down to change the values of R1 and R2.

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The input voltage is V1 = 10 Volts.
Total Resistance of Potentiometer = Rpot = Ohms.       0 10
Call the resistance above the slider R1 = Ohms, and the resistance below is R2 = Ohms.
These two resistance form a voltage divider, with output voltage $V2 = V1 \frac {R2}{R_{pot}} = V1 \frac {R2}{R1 + R2}$ = Volts.

The current is $I=\frac{V1}{R_{pot}}=\frac{V1}{R1+R2}=$ Amps