حلول التدريبات العملية 1- قانون الشغل والطاقة

4. 4.1-

حسب تعريف الشغل:

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في هذه الحالة ، تعمل القوة في اتجاه عكس الحركة ، وقيمة الزاوية ? هي 180 درجة.

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