Arduino Forum

Using Arduino => General Electronics => Topic started by: patgeek2019 on Nov 11, 2019, 10:48 pm

Title: direction of electricity in arduino
Post by: patgeek2019 on Nov 11, 2019, 10:48 pm
the direction of electricity on arduino, is it direct current?, which that means  the displacement of negative electrons from the negative to the positive. It is why  resistance  is between led and ground
Title: Re: direction of electricity in arduino
Post by: hammy on Nov 11, 2019, 11:05 pm
Yes and then no ( you can put the resistor either side ; if in understand you correctly )


You need to learn about basic circuit theory , voltage , current , ohms law .
Title: Re: direction of electricity in arduino
Post by: PerryBebbington on Nov 11, 2019, 11:22 pm

Quote
The direction of electricity on arduino, is it direct current?, which that means  the displacement of negative electrons from the negative to the positive. It is why  resistance  is between led and ground.
What Hammy said.

Electrons always flow from negative to positive, that's basic physics, nothing you can do about it. Positive charge carriers, for example cations, flow the other way from positive to negative.

None of this has anything to do with where you place the resistor in series with an LED (or anything else).

You need to learn:
Ohms Law (https://en.wikipedia.org/wiki/Ohm's_law)
Kirchoff's laws (https://en.wikipedia.org/wiki/Kirchhoff's_circuit_laws)
To get you started.
Title: Re: direction of electricity in arduino
Post by: Grumpy_Mike on Nov 11, 2019, 11:31 pm
If you think it matters which direction electric current flows then you don't really understand how electricity works.

In a series circuit it does not flow into one thing first and then flow into the next thing. All the elements or components in a series circuit experience the same flow of current at the same time. With no current flowing the charge carriers are all hanging about doing nothing. Then, when a voltage is applied they all start to drift at the same time.
Title: Re: direction of electricity in arduino
Post by: lastchancename on Nov 12, 2019, 01:05 am
Call in @GolamMustafa, hell describe everything.
Title: Re: direction of electricity in arduino
Post by: MarkT on Nov 12, 2019, 03:30 pm
The sign of charge is an arbitrary human convention, invented before electrons were discovered.  We talk of "conventional current" as flowing from positive to negative, you don't actually care whether the charge-carriers are +ve or -ve charges for circuit analysis at all.

It does matter for understanding semiconductors and electron tubes however.

In most situations we don't worry about the direction of the current anyway because it will be going one way only, we only care about how much.

Yes, we are dealing with DC here, logic circuits run off a 5V or 3.3V (or sometimes less) DC supply.
Title: Re: direction of electricity in arduino
Post by: patgeek2019 on Nov 12, 2019, 04:20 pm
thank you hammy

it was the only answer that helped me as a newbie in electronics