حلول التدريبات العملية 2 في الكهروستاتيكا

16. 6.2

كل واحدة من الشحنتين«math xmlns=¨http://www.w3.org/1998/Math/MathML¨»«mstyle mathsize=¨20px¨»«mo mathvariant=¨bold¨»§#160;«/mo»«msub»«mi mathvariant=¨bold¨»Q«/mi»«mn mathvariant=¨bold¨»2«/mn»«/msub»«mo mathvariant=¨bold¨»-«/mo»«mi mathvariant=¨bold¨»§#1493;«/mi»«mo mathvariant=¨bold¨»§#160;«/mo»«msub»«mi mathvariant=¨bold¨»Q«/mi»«mn mathvariant=¨bold¨»1«/mn»«/msub»«/mstyle»«/math»تعمل حقلًا كهربائيًا بالنقطة A  بنفس المقدار والاتجاه.

نُشير إلى الحقل الناتج من الشحنة Q1 بـ E1 والحقل الناتج من الشحنة Q2 بـ  E2.

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نحلل تحليلًا قائم الزاوية لمتجهي الحقل ونحصل على مركّبتي كل من الحقلين.  

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محصلة الحقلين بالاتجه Y تساوي صفر, الحقل المحصّل يساوي مجموع الحقلين في الاتجاه X :

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الشكل التالي يصف اتجاه متّجه محصلة الحقل بالنقطة A:

مقدار محصلة الحقل الكهربائي هو 121.78 نيوتن لكولون، واتجاهه نحو اليسار.