حلول التدريبات العملية الديناميكا لجسمين

يتحرك كلا الجسمين على طول السطحين المائلين.

لأن الجسمين موصولين بواسطة خيط مشدود، فإن تسارع كل منهما يكون متساوي المقدار.

لضمان أن يكون لتسارع كل منهما نفس الإشارة، نحدّد المحاور على النحو التالي:

بالنسبة للجسم 1: نقوم بتعيين المحور X لأسفل السطح المائل، والمحور Y متعامد على السطح.

بالنسبة للجسم 2: نحدد المحور X باتجاه السطح المائل لأعلى ، والمحور Y متعامد على السطح.

تعمل ثلاث قوى على الجسم 1:  قوة الجاذبية W₁ وقوة التوتر T والقوة العمودية N₁.

نرسم مخططًا للقوى المؤثرة على الجسم 1:

نحلل قوة الجاذبية لمركّبيها:

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نُشير للتسارع المشترك للجسمين بـ a.

نكتب معادلة الحركة للجسم 1 في اتجاه عمودي على السطح (اتجاه المحور y):

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نكتب معادلة الحركة للجسم 1 في اتجاه لأسفل السطح المائل (اتجاه المحور x الذي تم اختياره ليكون المحور الموجب): 

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تعمل ثلاث قوى على الجسم 2:  قوة الجاذبية W₂ وقوة الشد T والقوة العمودية N₂.

نرسم مخطط القوى التي تعمل على الجسم 2:

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