alternating current

The purpose of the current is to allow some work to be done. Please look up what RMS means.

Tom

The RMS voltage gives the same equivalent power in a purely resistive load as a DC voltage of that value.

Best regards,

Bob Masta DAQARTA v3.50 Data AcQuisition And Real-Time Analysis

Thamara: This is how I have understood it. Draw a sine wave. Look at it. Notice how the voltage (or current) starts at zero, peaks (to 1.41 times the RMS value) positive goes to zero and then peaks 1.41 times RMS negative. The RMS (Root Mean Square) value of the area within the sine wave can do the same amount of work (supply the same amount of power etc.) as a steady state DC voltage (or current) with the same value. For example suppose a DC value is say a steady unchanging 100. The equivalent sine wave would start at zero, rise to +141, decline to zero and then decline to -141. The RMS value of that rising and falling (alternating polarity voltage or current) would be the same; i.e. 100. A better explanation should be in any basic text book. Have fun.