# How do objects get the same amount of power from one port as it would from an extension cable that splits said port in 3 or 4, wouldn’t it just cut the power in half or in quarters giving less power to the object?

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How do objects get the same amount of power from one port as it would from an extension cable that splits said port in 3 or 4, wouldn’t it just cut the power in half or in quarters giving less power to the object?

In: Technology

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As others have said, devices *draw* current/power. An outlet can support some large amount of current/power, but it eon’t supply it unless a device is specifically drawing that amount of current/power

That’s why outlets are cool with nothing plugged in. Put your finger in there and you could draw just as much current as a few devices, and it isn’t pleasant.

Think about it this way, power lines don’t know how much you’ll use. But that’s ok, they’ll just send a huge amount and you can use what you need, and the rest gets rerouted

Current vs voltage. I’m going to use NZ values, US and Europe use different, and compare it to water.

Your wall plug can deliver 240volts at 10 amps – let’s call that a 240m high pipe and watertower that can flow at up to 10 gallons a second. Voltage is how much potential energy it has (240m of gravitational potential energy) amp/current is how fast it flows.

What your power board does is magically divide that 10 gallons into up to 4 potential pipes (4 point plug)

Plug your TV into one point – let’s say 3 amps at 240 volts. The power board makes one pipe that can deliver 3 gallons per second, rest is still sitting there ready. Take note, the height of the pipe didn’t change, only how much of the flow is being used, and only 3 gallons per second are flowing – rest is sitting there chillin.

Let’s plug in something else – a heater. High draw, let’s call it 5 amps. Height hasn’t changed, still delivering 240v, but now 8 gallons per second are being used.

Now I want to plug in something else – my xbox is three amps. Oh no, now we’re sitting at 11 gallons through a 10 gallon pipe!!! What happens? In short, the xbox pulls the water through faster than the pipe can handle. It’s like blowing up a balloon too hard – your cheeks start to hurt as they are doing too much! The wires, board and stuff start to heat up. This makes it harder for the power to flow, the power gets pulled harder, repeat until something melts and the circuit breaks.

Practically speaking, your fuses will blow before then – they detect too much water flowing and close. But a shit mulitboard, wiring or seized fuses happen – and fire.

Power equals voltage times current. There is two ways you can wire circuits, in series or in parallel. Wiring in parallel gives you constant voltage and wiring in series gives you constant current. All domestic circuits are wired in parallel and have the same voltage on the terminals. To give an example, lets say a load is rated at 230W. That divided by domestic voltage of 230V gives you 1A of current that this load consumes. Having the same voltage in one socket, and also in all 3 or 4 sockets in the extension lead is why the power doesn’t split, load takes as many current as it needs and that multiplied by voltage is the required power.

Most things don’t use the entire amount of current that a breaker can deliver. Don’t think of the power from an outlet like it’s a set amount… The amount of power being delivered from the outlet depends on how much power is required by the things plugged into it.

You only run into trouble if there’s enough load on a single circuit to trip the breaker. And you’ll see that happen if you’re microwaving, using the toaster, and running a few other kitchen appliances at the same time

A circuit is designed to handle a certain amount of current. Devices draw current depending on their need/electrical characteristics. Once the sum of current draws exceeds the current the circuit was designed for, the breaker breaks, or if there is no breaker a weaker component will melt, or burn.

The plugs are wired in parallel,the voltage will be the same at every socket and the current will be divided between them depending on the resistance of the appliance.

Take a narrow river. A few hundred elephant can drink the same amount (per second). When a million elephants drink it, where did all the water go?