Where to select the voltage from, from a voltage divider?

Question

I want to utilize 2.5V, from a 5V source.

This is a diagram:

My question is, where do I draw the 2.5 volts from?

Is it from the wire I painted pink, or from the wire I painted green?

Or it doesn't matter since the voltage in the sides of a resistor is the same?

I have to make sure.

Answer 1

^{simulate this circuit – Schematic created using CircuitLab}

Figure 1. An adjustable potential divider and the fixed equivalent potential divider when the wiper is in the centre position.

In both cases the voltage at the bottom is 0 V, at the top it's 5 V and in the middle it's 2.5 V.

The difference with the potentiometer is that it's adjustable. Turn the wiper to the bottom and you get zero volts. Slide it up and you can get any voltage you want between 0 and 5 V. It adjusts the "potential" (voltage) between the wiper and the terminals, hence "potentiometer".