كتاب Questions and Answers in Mechanical Engineering Part Two

Questions and Answers in Mechanical Engineering Part Two Prepared by Osama Mohammed Elmardi Suleiman Nile Valley University – Faculty of Engineering & Technology Question One Stress and Strain Explained with Types Stress is nothing but the force applied to the cross-sectional area and strain is nothing but change in dimensions of given material by original dimensions, after the load is applied. Think of a long bar, with one end fixed to a wall, and you’re pulling on the other end. Stress is how hard you’re pulling. The strain is how far the bar has stretched. Let us understand stress-strain in brief- Stress When anybody is subjected to external loading, then elements from the body will try to oppose that force, that internal resistance offered by elements from the body is known as stress. When force is applied to any deformable body which behaves as a continuum i.e. its mass is continuously distributed through the body, internal forces manifest inside the body. Quantitatively, stress is the average internal force acting upon a unit area of a surface within the body. Its SI unit is Pascal (N/m^2). In the context of three-dimensional bodies, there are two types of stresses, shear stress and normal stress. The former occurs as a reaction to body forces and the latter as a reaction to surface forces. Body forces act on the entire volume of the body e.g. gravitational force and surface forces act across a particular internal or external surface element of the body. Normal stress and Shear stress 2 Often in real life, most mechanical bodies experience both types of stresses simultaneously. Strain It is the ratio of change in dimension of the body due to external loading to original dimension of the body before loading. When force is applied to a body similar to the one described above, its configuration (set of positions of all particles of the body) tends to change. This is called deformation. It often involves a change in shape, but the definition of deformation
أسامة محمد المرضي سليمان - أسامة محمد المرضي سليمان ، مواليد مدينة عطبرة، ولاية نهر النيل-السودان في العام 1966 حاصل علي بكالوريوس الشرف في الهندسة الميكانيكية من كلية الهندسة بجامعة السودان للعلوم والتكنولوجيا في العام 1998. ماجستير في ميكانيكا المواد المركبة من جامعة وادي النيل عطبرة في العام 2003. ❰ له مجموعة من الإنجازات والمؤلفات أبرزها ❞ الإقتصاد الهندسي ❝ ❞ إنتقال حرارة وكتلة أمثلة محلولة ومسائل إضافية ❝ ❞ التوربينات الغازية Gas Turbines ❝ ❞ تحليل الجملونات (Analysis of Trusses) ❝ ❞ ديناميكا حرارية ❝ ❞ مجموعة من أشهر الأمثال العربية والإنجليزيةCollection of Famous English and Arabic Proverbs ❝ ❞ آلات هيدروليكية المضخات و التوربينات النصف قطرية و المحورية السريان ❝ ❞ أجهزة قياس Measurments INSTRUMENTATION ❝ ❞ تصميم الأنظمة الميكانيكية ❝ الناشرين : ❞ جميع الحقوق محفوظة للمؤلف ❝ ❞ جامعة وادى النيل ❝ ❱
من الهندسة الميكانيكية - مكتبة كتب الهندسة والتكنولوجيا.