Why is current flow opposite to electron flow?

Watch
MeZala
Badges: 2
Rep:
?
#1
Report Thread starter 6 years ago
#1
Current flow is from positive to negative and electron flow is from negative to positive.
Current is coulombs per seconds, coulombs are charge carriers which are electrons, so why is there an opposition of flow?


Posted from TSR Mobile
0
reply
Mr M
Badges: 20
Rep:
?
#2
Report 6 years ago
#2
(Original post by MeZala)
Current flow is from positive to negative and electron flow is from negative to positive.
Current is coulombs per seconds, coulombs are charge carriers which are electrons, so why is there an opposition of flow?


Posted from TSR Mobile
Electrons are negatively charged. If there is a negative flow of charge is one direction then this is effectively the same as a positive flow of charge in the opposite direction. I don't like your comment "coulombs are charge carriers" - you mean "Coulombs are units of charge".
0
reply
uberteknik
  • Study Helper
Badges: 21
Rep:
?
#3
Report 6 years ago
#3
(Original post by MeZala)
Current flow is from positive to negative and electron flow is from negative to positive.
Current is coulombs per seconds, coulombs are charge carriers which are electrons, so why is there an opposition of flow?


Posted from TSR Mobile
The difference arises because of a historical error:

Actual electron flow is from the -ve terminal to the +ve terminal. Conventional current is defined the other way around.

BEFORE the discovery of the electron and hence electric current, scientific thinking in the 17th/18th centuries had described electricity as a flow of charge.
Then, when Benjamin Franklin made an assumption that charge flowed from smooth wax to rough wool in the mid 1700's, his convention became established to the extent that it was too difficult to change by the time actual electron flow was discovered well over a century later. (Batteries, electric motors, electric lights, telegraph etc. were all in widespread use in the latter part of the 19th century.)

Hence the difference between electron-flow and the so-called historical conventional-current flow.

In reality, for almost all electrical calculations, it makes no difference which way, as long as all of the calculations are performed using the same reference direction. But, because of that original erroneous assumption, we still use conventional current flow today.

However, it is essential to know the reality of electron flow when understanding and dealing with physics at the atomic scale.
1
reply
Stonebridge
Badges: 13
Rep:
?
#4
Report 6 years ago
#4
It's also worth noting that current isn't always a flow of negative charge. In an electrolyte solution charge carriers are both positive and negative.
In a beam of protons or alpha particles, the flow of charge is positive.
0
reply
teachercol
Badges: 9
Rep:
?
#5
Report 6 years ago
#5
A positive current is the way positives move
A negative current is the way negatives move

Whats the problem?
0
reply
X

Quick Reply

Attached files
Write a reply...
Reply
new posts
Back
to top
Latest
My Feed

See more of what you like on
The Student Room

You can personalise what you see on TSR. Tell us a little about yourself to get started.

Personalise

Do you have the space and resources you need to succeed in home learning?

Yes I have everything I need (256)
56.89%
I don't have everything I need (194)
43.11%

Watched Threads

View All
Latest
My Feed