Unfortunately, the highly functional configuration of an authentic wok is incompatible with the heating surface of an electric stove-top or cook-top. The area of contact between this rounded vessel and a flat surface is small, and therefore heat is severely limited. Yet, a genuine wok must have a rounded bottom as a matter of practicality. Stir-frying is best executed with a small amount of cooking oil concentrated in the hottest zone, the heart of the wok, and a concave pan accomplishes this goal. In addition, the combination of the height and slope of the sides facilitates tossing, an essential stir-frying procedure.
Electric ranges (and electric woks, too) are ill suited for stir-frying for yet another reason. Many a stir-fry recipe calls for a quick lowering or raising of the temperature in the middle of the cooking period. Electric heating units generally respond slowly to temperature adjustments.
Do not buy one of those "woks" that has been designed with a flat bottom specifically for use on an electric unit. You cannot properly stir-fry in one of these vessels, which are essentially high-walled skillets. The rounded bottom is required for true Chinese stir-frying.