??? ?? ??????? ???? ?? ???? ???? ?????? ???? ???? ????? ???? ????? ????? ????? ?? ???? ?????????? ????????: ???? ?? ??????? ??? ??????? ??? ???????? ?????? ?? ??????? ??????? ?????.On account of eddy currents induced inside the steel, a sign is detected when steel is current. The fact that every steel has another section reaction when exposed to al