حلول التدريبات العملية حفظ كمية الحركة

نجد مقدار سرعة الجسم V في نهاية تأثير القوة F. حسب تعبير الدفع وكمية الحركة: 

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نعوّض معطيات السؤال ونعبر عن السرعة النهائية من تعبير V:

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