Understanding AbV, AbA, and AbOhm: CGS Units

abampere
abohm
abvolt
cgs
electromagnetism

This article explores the units AbV (Abvolt), AbA (Abampere), and AbOhm, which are part of the CGS (Centimeter, Gram, Second) system of units, particularly within electromagnetism. We’ll compare them to their counterparts in the more commonly used SI (International System of Units).

The Two Systems: SI and CGS

Before diving into the specifics, let’s quickly recap the two systems of measurement:

  • SI (International System of Units): The globally recognized standard system, employing units like meters, kilograms, and seconds.
  • CGS (Centimeter, Gram, Second): An older system, where the base units are centimeters for length, grams for mass, and seconds for time.

AbV (Abvolt)

What is an Abvolt?

The full name of AbV is Abvolt. It’s a unit used to measure Electromotive Force (EMF), which you can think of as a potential difference, within the CGS electromagnetic system. In essence, 1 abV is the potential needed to drive a current of 1 abA through a resistance of 1 abΩ.

Applying Ohm’s Law to CGS

Remarkably, the familiar Ohm’s Law applies to the CGS system as well:

E = I * R

Where:

  • E is the EMF in abvolts
  • I is the current in abamperes
  • R is the resistance in abohms

AbA (Abampere)

What is an Abampere?

The full form of AbA is Abampere, and this unit measures electrical current in the CGS system of electromagnetic units.

How is Abampere Defined?

The current, I is defined as rate of change of charge: I=dQ/dT. One Abampere is equivalent to one abcoulomb of charge passing a specific point within one second.

Abamperes vs. Amperes

You might be familiar with smaller current units like milliamperes (mA) and microamperes (µA) which are subdivisions of the Ampere. In contrast, the abampere is a larger unit of current than the Ampere, with the following relationship:

  • 1 mA = 10^-3^ A
  • 1 µA = 10^-6^ A
  • 1 abA = 10 A

AbΩ (AbOhm)

What is an AbOhm?

AbOhm is the unit for electrical resistance in the CGS electromagnetic system.

Abohms vs. Ohms

In contrast to abAmperes, which are large compared to Amperes, abOhms represent a smaller unit of resistance compared to Ohms. The conversion is as follows:

  • 1 abΩ = 10^-9^ Ω

The Relationship

As we said earlier, when a current of 1 abA flows through a resistance of 1 abΩ, a potential difference of 1 abV will exist across the component. This neatly ties the three units together!

Summary: Key Differences

UnitFull NameMeasuresSystemSize (relative to SI)
AbVAbvoltEMFCGSRelated to other CGS
AbAAbampereCurrentCGS10x larger than Ampere
AbΩAbOhmResistanceCGS10^-9^x smaller than Ohm
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