حلول الممارسات – 1 – الإستمرارية

13. ג.2.3

لكي يتحرّك الجسم إلى أسفل المستوى المائل، يجب أن تكون زاوية ميل المستوى أكبر (بمقدارٍ ما) من الزاوية التي يكون عندها الجسم في حالة عتبة الحركة.

سنحسب زاوية ميل المستوى عندما يكون الجسم عند عتبة الحركة.

عند عتبة الحركة تكون قوة الاحتكاك الساكن هي قوة الاحتكاك الساكن العظمى. وبناءً على ذلك سنرسم مخطط قوى مناسبًا.

الجسم في حالة سكون، ووفقًا للقانون الأول لنيوتن فإن محصّلة القوى المؤثِّرة على الجسم تساوي صفرًا.

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سنُعوِّض قوة الضغط العمودية (قوة النورمال) من معادلة الحركة على المحور في معادلة الحركة على المحور X.

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