حلول التدريبات العملية الديناميكا لجسمين

7.1. قوة خارجية تعمل على الخيط

من القانون الثالث لنيوتن، القوة المؤثرة على الخيط تساوي القوة التي يُشغلها الخيط ، لذلك يمكننا القول إن قوةشد الخيط هي M₁g.

T = M₁g

4 قوى تؤثر على الجسم 2:  قوة الشد T وقوة الاحتكاك f_k وقوة الجاذبية W₂ والقوة العمودية N.

لنرسم مخططًا للقوى المؤثرة على الجسم 2:

نكتب معادلات الحركة للجسم 2 :

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