Open-circuit voltage

Okay kiddo, imagine you have a toy car and you put a battery in it. Now, you don't turn the car on and the wheels don't move, right? That's because the circuit is "open," meaning the electricity can't flow through the entire circuit because there's no complete path for it to follow.

Open-circuit voltage is a term used to describe the voltage or electrical potential difference when there is no complete circuit (or no load) attached to a power source, like a battery. In other words, it's the maximum amount of voltage that a battery can generate if nothing is connected to it.

Think of it like a water bottle. If there's no straw or spout for the water to flow through, the water will just sit there in the bottle, not going anywhere. The water is like electricity and the straw or spout is like a complete circuit.

So, open-circuit voltage is the "pressure" or "push" that a battery can provide when it's not connected to anything. But, just like how the water won't flow without a straw or spout, the electricity won't do anything without a complete circuit.