[Elecraft] k2-100??

[Stuart Rohre]

Power is Voltage, (E) times Current, (I).  Since E is I  times  Impedance,
(Z);

Power becomes I squared times Z, where Z is the load, 50 ohms.  Multiply the
RF current reading times 50 ohms to get the power in the dummy load.

Now, if you are measuring DC current, that DC Power is simply I times E.
72, Stuart K5KVH