1 Volt can be defined as 1 Joule / Coulomb.
1 Ampere can be defined as 1 Coulomb / second.
1 Ohm is the resistance if 1 Ampere is in a material when 1 Volt is applied.
How would we define 1 Ohm algebraically like we just did with 1 Volt and 1 Ampere?
>>382915
We don't: almost all the electrical units are derived from mechanical units, to avoid this circular definition.
>>382919
Oh, okay--thank you.
>>382915
See https://en.wikipedia.org/wiki/SI_base_unit and https://en.wikipedia.org/wiki/SI_derived_unit. Note that being a "base unit" doesn't mean it's not derived from anything, it just means it's a convenient unit to calibrate against the real world. You can derive the entire of SI after arbitrarily defining what a second, a kilogram and a Kelvin are.
For example, you can use a the speed of a photon to measure a meter. So you can now accelerate a kilogram to find out what a Newton is.
This means you can now place two conductors a meter apart in a vacuum and measure an Ampere.
You can also apply a Newton to something over a Metre, and get a Joule.
From Joules and Amps, you can get Watts, Volts and Ohms.
The definitions all work, because you can trace them all back to kilograms, seconds, and/or kelvin.