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Ohm's law: $$V=IR$$

Here $I$ is the current in the circuit, which is equal to charge flowing per unit time.

$R$ is the resistance offered. $V$ is potential difference.

What's the physical significance of potential difference in a circuit? I mean, how does it even arise?

Steeven
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user123844
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1 Answers1

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Potential difference (or voltage) is equivalent to a pressure difference in a pipe system of water.

  • If there is equal pressure at two points, then no water has any reason to move. If there is a difference, water flows (is pushed) towards lower pressure.
  • Similarly, charges will want to move towards the point of lowest possible potential. The larger the potential difference, the larger the "pressure" is pushing these charges.

Here's something for the intuition.

The origin of potential is quite straight forward:

  • Charge of equal sign repels each other. If you move many electrons, for example, together they will push on each other to move away.
  • Imagine having much charge in one end of a wire and less charge in the other end. Then the repulsion is larger where there is more charge, and it will be pushed to the other end - it will as well be repelled from this other end, but less.

This potential difference is the sole reason that any current is flowing at all.

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Steeven
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