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An Ohm is a unit of measure that quantifies the impedance of charge flow. The "Ohm" itself does not impede the flow, but indicates the ratio of voltage to current which indicates the "resistance" or "impedance" to charge flow. Hence, the unit of "Ohm" is also the unit of Volts/Amp.
Intuitively, a larger number of Ohms implies a larger number volts needed to drive every Amp of charge flow through a material that impedes the flow.
It sounds like your questions naturally leads to "What does impede charge flow?". This is not straightforward to answer, but there are many simplified discussions about this if you do a google search. Perhaps the simplest answer could be, that resistance is caused by free electrons colliding with atoms which generates heat, which is an energy loss. This would not cover all cases and is highly simplified from a physics point of view, but perhaps it is a beginning to you finding your answer.
There are similarities; however, my tendency is to say that's not the right way to visualize it.
Let's try a different approach.
First, let's ask the reverse question. What causes conduction? Conduction is allowed by free charges (usually free electrons in wires) that can move. Once we understand that, we can ask, "Why don't they move unimpeded?".
Well, the electrons are in thermal motion at high speed and they move until they hit an atom. Hence, although the electrons are free to move due to the force from voltage, they are already moving at high speed due to thermal energy, and they will collide and stop very quickly because of thermal collisions.
In a circuit, a voltage causes an electric field which puts a force on the electrons to drift along the wire, while moving thermally. The thermal motion is fast, but the drift speed is slow. But, obviously, there is a process that prevents the free unimpeded motion of the electrons, and this is what resistance is. The thermal collisions are basically killing the motion that the voltage is trying to put on the free electrons. That's why metals have higher resistance as temperature increases.
A good lecture on the explanation and a simple mathematical model can be found here. The first 15 minutes covers what you are asking.
**broken link removed**
You'll note that even Prof. Lewin mentions that this is a simplified model, and not entirely correct from a physics viewpoint. However, it is the best intuitive model I know of.
Think of it as a large drum full of water (full of electrons) with a hole in the bottom. A smaller hole has higher resistance (ohms in electrical terms or movement of electrons) as less water flows (electrons) through it. Compare that with a larger hole which having a lower resistance allows more water (electrons) to flow through it.
If you are at this stage of understanding of current flow and basic electricity, then I suggest you forget the concept of Q dampening for the moment.
Most basic concepts of electrical current flowing and resistance can easily be understood as water flowing through pipes of various diameters.
e.g in simple terms..
Q. How does an earth leakage circuit breaker work with my electric fire?
A. What flows into an electric fire through the live wire must be the same as what flows back through the neutral wire (Kirchoff's law). If not there is a fault.
With water, what flow into a radiator must be the same as what comes out. if not, you have a leak resulting in a puddle of leakage (electrons). Another fault. An earth leakage breaker detects the presence of a leak.
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