حلول التدريبات العملية 2 في الكهروستاتيكا

وبما أن القوة الكهربائية فقط هي التي تبذل شغل، يتم حفظ الطاقة الميكانيكية، نكتب معادلة حفظ الطاقة:

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يبدأ الجسم بالحركة من حالة السكون، وبالتالي فإن طاقة حركة الجسم في النقطة B تساوي صفرًا.

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نعبّر عن سرعة الجسم في النقطة A من معادلة حفظ الطاقة: 

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