102. יא.3.3

سنكتب معادلة الحركة للسلك حسب القوى المؤثرة عليه: 



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التيار عمودي على اتجاه الحقل المغناطيسي وبالتالي فإن «math xmlns=¨http://www.w3.org/1998/Math/MathML¨»«mstyle mathsize=¨20px¨»«mi mathvariant=¨bold¨ mathcolor=¨#0000FF¨»§#945;«/mi»«mo mathvariant=¨bold¨ mathcolor=¨#0000FF¨»=«/mo»«mn mathvariant=¨bold¨ mathcolor=¨#0000FF¨»90«/mn»«mo mathvariant=¨bold¨ mathcolor=¨#0000FF¨»§#176;«/mo»«/mstyle»«/math» , نعبر عن شدة التيار في السلك:

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