current

[muskan]

Please explain me the exact mechanism of current flow.

[DrP]

'exact' mechanism depends on the level of explanation you want - homework help section suggest school. I don't know what depth they are teaching such things at in your school, so:

 

Start with looking at potential difference. This is from the BBC GCSE website about current and voltage http://www.bbc.co.uk/schools/gcsebitesize/science/add_aqa/electricity/circuitsrev5.shtml

Edited July 11, 2017 by DrP

[Country Boy]

It also depends upon what type of "current" you are talking about. Water? Electricity?

Edited July 15, 2017 by Country Boy

[muskan]

electrical

[DrP]

electrical

 

then checkout the link I posted.

 

 

"Potential difference (voltage)

A potential difference, also called voltage, across an electrical component is needed to make a current flow through it. Cells or batteries often provide the potential difference needed."

[LabRat1]

The flow of electrons due to a potential difference at the ends of a conductor is current.

 

 

Quote

 

 

Edited July 23, 2017 by LabRat1

[oliviawilliams]

Electrons are move in a conductor when there is some pontential difference across its end.

I think you should go on search engines or wikipidia,quora.you can easily understand current flow

 https://en.wikipedia.org/wiki/Electric_current

[EdEarl]

Electrical current flows in different things differently. Among the easiest to understand is current flowing through a vacuum, for example in a vacuum tube (pre-transistor technology).

Electrons flow from the hot cathode to the anode when a potential difference (voltage) is applied across the cathode (-) and anode (+). By convention (tradition) current flow is opposite electron flow in a vacuum tube.

[studiot]

Quote

Ed Earl

Electrical current flows in different things differently.

Just so true.

 

If Muskan does not know what an electrical current is, then he may well not know what a potential difference is either.

A potential difference is often called a 'voltage', but you have to be careful to find out if something external is providing the voltage (eg a battery) or whether there is an internal voltage created.

The first type of electrical current to study (there are others) is carried by moving electrons.

So there must be a source of electrons that can move about.

 

These can be generated by applying heat or light or enough externally applied voltage to a physical object.

 

Left on their own a collection of mobile electrons will just drift about, trying to get away from each other since they all carry the same negative charge.

(Remember like charges repel)

Heat and light do not move the electrons in any particular direction, but applying a voltage does.

This voltage drives the electrons away from the negative terminal and towards the positive one.

The greater the voltage the bigger the effect.

I also said that applied voltage can release mobile electrons. This is how we get sparks and the discharge in flourescent electric light fittings.

So applying a voltage directs the current in a way that we want.

Doing this is often likened to water in a hosepipe, but it is a very bad analogy because if you cut an electric cable, the current stops instantly at the cut.

But water will trickle out of a cut hosepipe for a long time after cutting.

 

If you understood this we can move on to other forms of electric current, in some of the different things Ed Earl mentioned (or perhaps he will tell you)

 

[EdEarl]

Good job studiot,  continue.

[LabRat1]

6 hours ago, studiot said:

If Muskan does not know what an electrical current is, then he may well not know what a potential difference is either.

She*

You're welcome 

[studiot]

24 minutes ago, LabRat1 said:

She*

You're welcome 

My mistake. Thank you.