حلول التدريبات العملية الديناميكا لجسمين

جسمان موصلان بخيط يتحركان عموديًا في اتجاهين متعاكسين.

لضمان أن يكون لتسارع كل منهما نفس الإشارة، نقوم باختيار المحور Y للجسم 1 لأسفل والمحور Y للجسم 2 لأعلى.

تؤثر قوتان على كل جسم:  قوة الجاذبية W وقوة التوتر T₁.

(من المهم أن نتذكر أن قوة الشد هي نفسها في كلا الطرفين، على الرغم من أن الخيط يمر حول البكرة - عندما يتم إهمال قوى الاحتكاك بين الخيط والبكرة وعندما يتم إهمال كتلة الخيط).

نرسم مخططًا للقوى المؤثرة على الجسم 1: 

نكتب معادلات الحركة للجسم 1 باتجاه المحور :Y  

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نرسم مخطّط القوى التي تعمل على الجسم 2:

نكتب معادلات الحركة للجسم 2 باتجاه المحور :Y 

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نجمع التعبيرين 1 و 2 للتوتر ونعبر عن التسارع   :a

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