Franklin second to Teraampere volt per ohm

Franklin (1706–1790) was the American polymath who proved lightning is electrical with his famous kite experiment in 1752. He introduced the convention of "positive" and "negative" charge that we still use today. He arbitrarily assigned positive to the charge on glass rubbed with silk — which turned out to be a deficit of electrons, giving us the unfortunate convention that current flows opposite to electron motion.

The roentgen (R) was defined in 1928 as the radiation exposure producing 1 ESU of charge (1 franklin ≈ 3.336 × 10⁻¹⁰ C) per cm³ of dry air at STP. This CGS-era definition stuck because radiation safety regulations were already built around it. Even though the SI gray replaced the roentgen for dosimetry, the roentgen — and its franklin-based definition — persists in US regulatory and medical imaging contexts.

The legacy unit of radiation exposure, the roentgen (R), is defined as the amount of X-ray or gamma radiation that produces 1 esu of charge (1 franklin) per cubic centimeter of dry air at STP. This definition dates from the 1920s when CGS-ESU was standard. Modern dosimetry uses grays and sieverts, but the roentgen and its franklin-based definition persist in some medical and regulatory contexts.

One Fr/s is about 0.33 nanoamperes — less current than a sleeping microcontroller draws. To equal the 1 A flowing through a phone charger cable, you would need about 3 billion franklins per second. The unit is spectacularly impractical for anything beyond electrostatics calculations.

Sort of. He labelled the charge on glass rubbed with silk as "positive," not knowing it was caused by removing electrons. When Thomson discovered the electron in 1897, it turned out electrons carry what Franklin called negative charge. So conventional current flows from + to −, opposite to actual electron flow. Engineers and physicists have lived with this "mistake" for over 250 years.

Possibly. Astrophysical jets from active galactic nuclei are theorised to carry currents of 10¹⁷–10¹⁸ amperes — millions of teraamperes — flowing along magnetic field lines spanning thousands of light-years. Pulsar magnetospheres may sustain teraampere-class currents in their polar regions. On Earth, nothing comes remotely close.

The notation makes the derivation from Ohm's law explicit: I = V/R, scaled by tera. It appears in pedagogical contexts showing that SI prefixes apply consistently to derived expressions, and in astrophysics papers where the V/Ω form reminds readers of the physical relationship producing the current — a voltage driving charge through a resistance.

Even through a superconductor (zero DC resistance), you would need enormous energy to establish the magnetic field of a teraampere current. Through a 1 Ω resistor, Ohm's law says you would need 10¹² volts (1 teravolt). The power dissipated would be 10²⁴ watts — about 2.6 million times the Sun's total luminosity. The wire would not survive.

In astrophysical jets and magnetospheres, charged plasma flows along magnetic field lines over enormous cross-sections — millions of square kilometers. Even modest current densities, integrated over these vast areas, yield teraampere total currents. The plasma is the conductor, and the "voltage" comes from the rotating magnetic field of the central object.

The gigaampere (GA, 10⁹ A) fills that gap but is almost never used. No terrestrial phenomenon or experiment reaches gigaampere levels. The jump from megaampere (achievable in pulsed-power labs) to teraampere (astrophysical only) reflects a genuine gap in nature — there is simply nothing on Earth that produces currents between 10⁶ and 10⁹ amperes.