حلول التدريبات العملية 3- مسارات رأسية

الحد الأدنى للارتفاع الذي يجب أن يتحرر منه الجسم من حالة السكون هو الارتفاع الذي ستكون فيه سرعة الجسم في النقطة C مساوية  «math xmlns=¨http://www.w3.org/1998/Math/MathML¨»«msub»«mi mathvariant=¨bold-italic¨ mathcolor=¨#0000FF¨»V«/mi»«mi mathvariant=¨bold¨ mathcolor=¨#0000FF¨»C«/mi»«/msub»«mo mathvariant=¨bold¨ mathcolor=¨#0000FF¨»=«/mo»«msqrt mathcolor=¨#0000FF¨»«mi mathvariant=¨bold¨»g«/mi»«mo mathvariant=¨bold¨»§#183;«/mo»«mi mathvariant=¨bold¨»R«/mi»«/msqrt»«/math»

نعبّر عن هذا الارتفاع من معادلة حفظ الطاقة: 

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يبدأ الجسم في التحرك من حالة السكون ، فليس لديه طاقة حركية في النقطة  A.

ارتفاع النقطة C  يساوي ضعف نصف قطر الدوران.  

وبناءً عليه نعبر عن ارتفاع تحرير الجسم اللازم لإكمال حركته.

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