حلول التدريبات العملية الطاقة بالجاذبية

أثناء حركة الجسم، فقط قوة الجاذبية هي التي تنجز شغلًا، لذلك يتحقق قانون حفظ الطاقة الميكانيكية. 

نكتب معادلة حفظ الطاقة، ونستخدم تعبير طاقة وضع الجاذبية.

نقارن الطاقة الميكانيكية في النقطة A بالطاقة الميكانيكية في النقطة C :

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نكتب معادلة الطاقة بطريقة مفصّلة، ونعبر منها عن سرعة الجسم في اللحظة التي يصيب فيها الأرض (V_c). 

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