حلول التدريبات العملية حفظ كمية الحركة

نستخدم قانون الدفع وكمية الحركة لحساب سرعة الجسم في اللحظة t = 4s:

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اتجاه متجه السرعة نحو اليمين في الاتجاه الموجب.