4. جسمان معلقان بواسطة بكرة

4.2. قوة الشد بالخيط بين الجسمين

نستخدم إحدى المعادلات المشار لها في القسم السابق:

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نعوّض التسارع الذي وجدناه ونعبر عن قوة الشد T:

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