In AC, the current and voltage is measured in what is known as 'Root-means-Squared.' This is a complicated mathematic way of measuring AC current and voltage in 'DC equivalent' numbers when using a resistive load. If you look at a 120V AC signal on an oscilloscope, the voltage peaks are at 170V.
Note Root-Means-Squared can be thought of as the average..... but it is not really an average. The mathematical average of an AC voltage or current is zero.
The net result is that if you have 100V going through a 100-ohm resister it results in 1 amp regardless of AC or DC. It also burns 100W in both AC and DC.
However, When the load is inductive or capacitive, the equivalency starts breaking down.