The content of ohm's law is that the current in a conductor is directly proportional to the voltage at both ends of the conductor and inversely proportional to the resistance of the conductor; The mathematical expression is I = ur.

The unit of current is ampere, which is represented by symbol A; The unit of voltage is volts, which is represented by the symbol V; The unit of ohm is ohm, which is represented by the symbol ω;

So the answer is: I = ur ampere (a); Volts; Ohm (ω).