حلول التدريبات العملية 3- مسارات رأسية

أثناء حركة الجسم من النقطة A إلى النقطة C ، فقط قوة الجاذبية هي التي تبذل شغلًا، ويتحقق حفظ الطاقة الميكانيكية.

نجد سرعة الجسم في النقطة C باستخدام معادلة حفظ الطاقة: 

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يتحرك الجسم من حالة السكون، وبالتالي فإن الطاقة الحركية في النقطة A تساوي صفرًا. ارتفاع النقطة A يساوي R1. ارتفاع النقطة C يساوي R2.

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