حلول التدريبات العملية 1- قانون الشغل والطاقة

10. 1.2-

حسب تعريف الشغل:

«math xmlns=¨http://www.w3.org/1998/Math/MathML¨»«mi mathvariant=¨bold-italic¨ mathcolor=¨#0000FF¨»W«/mi»«mo mathvariant=¨bold¨ mathcolor=¨#0000FF¨»=«/mo»«mrow mathcolor=¨#0000FF¨»«mo stretchy=¨true¨ mathvariant=¨bold¨»|«/mo»«mover»«mi mathvariant=¨bold¨»F«/mi»«mo mathvariant=¨bold¨»§#8594;«/mo»«/mover»«mo stretchy=¨true¨ mathvariant=¨bold¨»|«/mo»«/mrow»«mo mathvariant=¨bold¨ mathcolor=¨#0000FF¨»§#183;«/mo»«mrow mathcolor=¨#0000FF¨»«mo stretchy=¨true¨ mathvariant=¨bold¨»|«/mo»«mover»«mrow»«mo mathvariant=¨bold¨»§#8710;«/mo»«mi mathvariant=¨bold¨»X«/mi»«/mrow»«mo mathvariant=¨bold¨»§#8594;«/mo»«/mover»«mo stretchy=¨true¨ mathvariant=¨bold¨»|«/mo»«/mrow»«mo mathvariant=¨bold¨ mathcolor=¨#0000FF¨»§#183;«/mo»«mi mathvariant=¨bold-italic¨ mathcolor=¨#0000FF¨»C«/mi»«mi mathvariant=¨bold-italic¨ mathcolor=¨#0000FF¨»O«/mi»«mi mathvariant=¨bold-italic¨ mathcolor=¨#0000FF¨»S«/mi»«mstyle mathvariant=¨bold¨ mathcolor=¨#0000FF¨»«mo stretchy=¨true¨»(«/mo»«mi»§#952;«/mi»«mo stretchy=¨true¨»)«/mo»«/mstyle»«mspace linebreak=¨newline¨/»«mspace linebreak=¨newline¨/»«/math»

شغل القوة  F:

اتجاه القوة F في اتجاه الحركة ، قيمة الزاوية ? تساوي 0 درجة. 

«math xmlns=¨http://www.w3.org/1998/Math/MathML¨»«msub»«mi mathvariant=¨bold-italic¨ mathcolor=¨#0000FF¨»W«/mi»«mi mathvariant=¨bold¨ mathcolor=¨#0000FF¨»F«/mi»«/msub»«mo mathvariant=¨bold¨ mathcolor=¨#0000FF¨»=«/mo»«mn mathvariant=¨bold¨ mathcolor=¨#0000FF¨»30«/mn»«mo mathvariant=¨bold¨ mathcolor=¨#0000FF¨»§#183;«/mo»«mn mathvariant=¨bold¨ mathcolor=¨#0000FF¨»40«/mn»«mo mathvariant=¨bold¨ mathcolor=¨#0000FF¨»§#183;«/mo»«mi mathvariant=¨bold-italic¨ mathcolor=¨#0000FF¨»C«/mi»«mi mathvariant=¨bold-italic¨ mathcolor=¨#0000FF¨»O«/mi»«mi mathvariant=¨bold-italic¨ mathcolor=¨#0000FF¨»S«/mi»«mrow mathcolor=¨#0000FF¨»«mo mathvariant=¨bold¨ stretchy=¨true¨»(«/mo»«mn mathvariant=¨bold¨»0«/mn»«mo mathvariant=¨bold¨ stretchy=¨true¨»)«/mo»«/mrow»«mo mathvariant=¨bold¨ mathcolor=¨#0000FF¨»=«/mo»«mn mathvariant=¨bold¨ mathcolor=¨#0000FF¨»30«/mn»«mo mathvariant=¨bold¨ mathcolor=¨#0000FF¨»§#183;«/mo»«mn mathvariant=¨bold¨ mathcolor=¨#0000FF¨»40«/mn»«mo mathvariant=¨bold¨ mathcolor=¨#0000FF¨»§#183;«/mo»«mrow mathcolor=¨#0000FF¨»«mo mathvariant=¨bold¨ stretchy=¨true¨»(«/mo»«mn mathvariant=¨bold¨»1«/mn»«mo mathvariant=¨bold¨ stretchy=¨true¨»)«/mo»«/mrow»«mo mathvariant=¨bold¨ mathcolor=¨#0000FF¨»=«/mo»«mn mathvariant=¨bold¨ mathcolor=¨#0000FF¨»1200«/mn»«mi mathvariant=¨bold-italic¨ mathcolor=¨#0000FF¨»J«/mi»«/math»

شغل قوة الاحتكاك f_k :

«math xmlns=¨http://www.w3.org/1998/Math/MathML¨»«msub»«mi mathvariant=¨bold-italic¨ mathcolor=¨#0000FF¨»W«/mi»«mi mathvariant=¨bold¨ mathcolor=¨#0000FF¨»F«/mi»«/msub»«mo mathvariant=¨bold¨ mathcolor=¨#0000FF¨»=«/mo»«mn mathvariant=¨bold¨ mathcolor=¨#0000FF¨»30«/mn»«mo mathvariant=¨bold¨ mathcolor=¨#0000FF¨»§#183;«/mo»«mn mathvariant=¨bold¨ mathcolor=¨#0000FF¨»40«/mn»«mo mathvariant=¨bold¨ mathcolor=¨#0000FF¨»§#183;«/mo»«mi mathvariant=¨bold-italic¨ mathcolor=¨#0000FF¨»C«/mi»«mi mathvariant=¨bold-italic¨ mathcolor=¨#0000FF¨»O«/mi»«mi mathvariant=¨bold-italic¨ mathcolor=¨#0000FF¨»S«/mi»«mrow mathcolor=¨#0000FF¨»«mo mathvariant=¨bold¨ stretchy=¨true¨»(«/mo»«mn mathvariant=¨bold¨»180«/mn»«mo mathvariant=¨bold¨ stretchy=¨true¨»)«/mo»«/mrow»«mo mathvariant=¨bold¨ mathcolor=¨#0000FF¨»=«/mo»«mn mathvariant=¨bold¨ mathcolor=¨#0000FF¨»30«/mn»«mo mathvariant=¨bold¨ mathcolor=¨#0000FF¨»§#183;«/mo»«mn mathvariant=¨bold¨ mathcolor=¨#0000FF¨»40«/mn»«mo mathvariant=¨bold¨ mathcolor=¨#0000FF¨»§#183;«/mo»«mrow mathcolor=¨#0000FF¨»«mo mathvariant=¨bold¨ stretchy=¨true¨»(«/mo»«mo mathvariant=¨bold¨»-«/mo»«mn mathvariant=¨bold¨»1«/mn»«mo mathvariant=¨bold¨ stretchy=¨true¨»)«/mo»«/mrow»«mo mathvariant=¨bold¨ mathcolor=¨#0000FF¨»=«/mo»«mo mathvariant=¨bold¨ mathcolor=¨#0000FF¨»-«/mo»«mn mathvariant=¨bold¨ mathcolor=¨#0000FF¨»1200«/mn»«mi mathvariant=¨bold-italic¨ mathcolor=¨#0000FF¨»J«/mi»«/math»

الشغل الكلي المنجز على الجسم:

«math xmlns=¨http://www.w3.org/1998/Math/MathML¨»«munderover mathcolor=¨#0000FF¨»«mo mathvariant=¨bold¨»§#8721;«/mo»«mrow/»«mrow/»«/munderover»«mi mathvariant=¨bold-italic¨ mathcolor=¨#0000FF¨»W«/mi»«mo mathvariant=¨bold¨ mathcolor=¨#0000FF¨»=«/mo»«msub»«mi mathvariant=¨bold-italic¨ mathcolor=¨#0000FF¨»W«/mi»«mn mathvariant=¨bold¨ mathcolor=¨#0000FF¨»1«/mn»«/msub»«mo mathvariant=¨bold¨ mathcolor=¨#0000FF¨»+«/mo»«msub»«mi mathvariant=¨bold-italic¨ mathcolor=¨#0000FF¨»W«/mi»«mn mathvariant=¨bold¨ mathcolor=¨#0000FF¨»2«/mn»«/msub»«mo mathvariant=¨bold¨ mathcolor=¨#0000FF¨»+«/mo»«mo mathvariant=¨bold¨ mathcolor=¨#0000FF¨»§#183;«/mo»«mo mathvariant=¨bold¨ mathcolor=¨#0000FF¨»§#183;«/mo»«mo mathvariant=¨bold¨ mathcolor=¨#0000FF¨»§#183;«/mo»«mo mathvariant=¨bold¨ mathcolor=¨#0000FF¨»§#183;«/mo»«mo mathvariant=¨bold¨ mathcolor=¨#0000FF¨»§#183;«/mo»«mspace linebreak=¨newline¨/»«munderover mathcolor=¨#0000FF¨»«mo mathvariant=¨bold¨»§#8721;«/mo»«mrow/»«mrow/»«/munderover»«mi mathvariant=¨bold-italic¨ mathcolor=¨#0000FF¨»W«/mi»«mo mathvariant=¨bold¨ mathcolor=¨#0000FF¨»=«/mo»«msub»«mi mathvariant=¨bold-italic¨ mathcolor=¨#0000FF¨»W«/mi»«mi mathvariant=¨bold¨ mathcolor=¨#0000FF¨»F«/mi»«/msub»«mo mathvariant=¨bold¨ mathcolor=¨#0000FF¨»+«/mo»«msub»«mi mathvariant=¨bold-italic¨ mathcolor=¨#0000FF¨»W«/mi»«msub mathcolor=¨#0000FF¨»«mi mathvariant=¨bold¨»f«/mi»«mi mathvariant=¨bold¨»k«/mi»«/msub»«/msub»«mo mathvariant=¨bold¨ mathcolor=¨#0000FF¨»=«/mo»«mn mathvariant=¨bold¨ mathcolor=¨#0000FF¨»1200«/mn»«mo mathvariant=¨bold¨ mathcolor=¨#0000FF¨»+«/mo»«mstyle mathvariant=¨bold¨ mathcolor=¨#0000FF¨»«mo stretchy=¨true¨»(«/mo»«mrow»«mo»-«/mo»«mn»1200«/mn»«/mrow»«mo stretchy=¨true¨»)«/mo»«/mstyle»«mo mathvariant=¨bold¨ mathcolor=¨#0000FF¨»=«/mo»«mn mathvariant=¨bold¨ mathcolor=¨#0000FF¨»0«/mn»«mo mathvariant=¨bold¨ mathcolor=¨#0000FF¨»§#160;«/mo»«mi mathvariant=¨bold-italic¨ mathcolor=¨#0000FF¨»J«/mi»«/math»