How can resistance affect voltage?

Question

Electronics

The greater the resistance of the device connected to the circuit, the greater the voltage. How does resistance affect voltage at the molecular level? Correct me if I'm wrong, I'm new.

Answer 1

Judging by your questions, you should look through textbooks on physics, from grades 7 to 11 of a secondary school.

The statement you wrote in the text of the question is a consequence of Ohm's law for a complete circuit, but is not a primary statement from which it is easy to explain the nature of electrical resistance.
The easiest case to understand is the electrical resistance of the metal:

The high electrical conductivity of metals is due to the fact that they contain a large number of current carriers - conduction electrons formed from valence electrons of metal atoms that do not belong to a specific atom. An electric current in a metal arises under the action of an external electric field, which causes an ordered movement of electrons. Electrons moving under the action of the field are scattered by inhomogeneities of the ionic lattice (on impurities, lattice defects, as well as violations of the periodic structure associated with thermal vibrations of ions). In this case, the electrons lose their momentum, and the energy of their movement is converted into the internal energy of the crystal lattice, which leads to heating of the conductor when an electric current passes through it.
In other media (semiconductors, dielectrics, electrolytes, non-polar liquids, gases, etc.), depending on the nature of the charge carriers, the physical cause of the resistance may be different. The linear relationship expressed by Ohm's law is not observed in all cases.

These are from Wikipedia.
For convenience of reasoning, we will accept that voltage is primary in this case - it forms an electric field that forces charge carriers to squeeze through the substance. Depending on how conductive this substance is, a current of one or another force is formed
.
The voltage across the resistance is the difference in excess pressure. Thus, when the tap is closed - the value of this difference is equal to the pressure in the water supply, gradually opening the tap, we reduce the difference in excess pressure, when fully open - to zero.

Answer 2

But I like another metaphor.
Imagine that you have a long corridor in your school (this is the conductor).
The corridor is full of schoolchildren wandering back and forth in it (these are electrons). On average, the current in the corridor is zero.
Suddenly (the bell rang) and new schoolchildren began to burst into the corridor from one end, driven by the desire to go the hell away from the class (minus the "batteries"). The pressure of schoolchildren is potential. It is different at the beginning and at the end of the corridor.
Schoolchildren press from one end, and the other end of the corridor is open to the street (plus).
The potential difference (pressure) between the beginning and the end of the corridor is the voltage.
Imagine that chairs were randomly arranged in the corridor before the bell.
Chairs interfere - this is resistance. Schoolchildren stumble, break chairs, heat up the situation (part of the energy of the desire of schoolchildren to take a walk is spent on this).
The more chairs, the greater the pressure difference between schoolchildren at the beginning and end of the corridor.
This was Ohm's law for the chain section.
On the example of schoolchildren, it is easier to explain than on the example of hydraulics. So you can talk about semiconductors, transistors, Kirchhoff's rule ... whatever.

Answer 3

totorialman , this is the effect of the internal resistance of your voltage source:

The more current the voltmeter consumes to measure the voltage, the more voltage is "lost" on the internal resistance of your source.