Definition of ampere in terms of a flow of electrons past a point in a wire?

Click For Summary
SUMMARY

An ampere is defined as the flow of one coulomb of electric charge per second, which translates to approximately 6.242 x 1018 electrons passing a point in a wire each second. The operational definition of an ampere, based on coulombs, is favored over the previous definition involving the force between two currents due to its clarity and direct measurement capability. This shift reflects a broader trend in physics towards definitions grounded in fundamental constants.

PREREQUISITES
  • Understanding of electric charge and its unit, Coulomb.
  • Basic knowledge of electron properties and charge quantification.
  • Familiarity with the concept of current in electrical circuits.
  • Awareness of historical definitions of electrical units.
NEXT STEPS
  • Research the historical definitions of electrical units, focusing on the ampere and coulomb.
  • Explore the implications of using fundamental constants in defining electrical measurements.
  • Learn about the role of the International System of Units (SI) in standardizing electrical measurements.
  • Investigate the relationship between current, voltage, and resistance using Ohm's Law.
USEFUL FOR

Students studying physics, electrical engineers, educators in the field of electronics, and anyone interested in the foundational concepts of electrical measurements.

pokeefer
Messages
41
Reaction score
0

Homework Statement



a.) What is the operational definition of an ampere?

b.) What is the definition of an ampere in terms of a flow of electrons past a point in a wire?

c.) What is the advantage of the operational definition over the definition in (b)?

Homework Equations



N/A

The Attempt at a Solution



I already defined part a.

I'm stuck on part b and c.

Thanks.
 
Physics news on Phys.org
An Ampere is 1 Coulomb of charge flowing per second. You can easily find the number of electron charges in a Coulomb because the electron charge is given in units of Coulombs.

I seem to recall this being in the news recently. I think they are tossing the definition of an Ampere in terms of the force between two currents and going with the Coulomb per second.
 

Similar threads

  • · Replies 8 ·
Replies
8
Views
2K
Replies
4
Views
2K
  • · Replies 3 ·
Replies
3
Views
2K
Replies
3
Views
3K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 4 ·
Replies
4
Views
3K
  • · Replies 7 ·
Replies
7
Views
2K
  • · Replies 5 ·
Replies
5
Views
2K
Replies
2
Views
1K
  • · Replies 5 ·
Replies
5
Views
2K