ไฟฟ้าและแม่เหล็ก

กระแสไฟฟ้า <div data-theme="light" style="width:0%" aria-valuemax="100" aria-valuemin="0" aria-valuenow="0" role="progressbar" class="css-1tbfdvy"> <svg viewBox="0 0 24 24" focusable="false" class="chakra-icon chakra-accordion__icon css-ce07eo" aria-hidden="true">

ทฤษฎีแม่เหล็กไฟฟ้า <div data-theme="light" style="width:0%" aria-valuemax="100" aria-valuemin="0" aria-valuenow="0" role="progressbar" class="css-1tbfdvy"> <svg viewBox="0 0 24 24" focusable="false" class="chakra-icon chakra-accordion__icon css-ce07eo" aria-hidden="true">