هذه رسائل تلغرافية في الهندسة الوصفية لطلاب الفرقة الإعدادية .
Messages in Descriptive Geometry
وفقنا الله وإياكم في الامتحان
Messages in Descriptive Geometry
وفقنا الله وإياكم في الامتحان
A control unit is the part of a CPU or other device that directs its operation.
A component of a microprocessor chip used for arithmetic, comparative, and logical functions.
Computers can be classified as supercomputers, mainframes, superminicomputers, minicomputers, workstations, microcomputers, or PDAs.
First-generation computers : were based on vacuum tubes.
Second-generation computers: were those in which transistors replaced vacuum tubes.
Third-generation computers: were those in which integrated circuits replaced transistors.
Fourth-generation computers: are those, such as microcomputers, in which large-scale integration (LSI) enabled thousands of circuits to be incorporated on one chip.
Fifth-generation computers: are expected to combine very-large-scale integration (VLSI) with sophisticated approaches to computing, including artificial intelligence and true distributed processing.الشيء المثير أن
an electronic device which is capable of receiving information (data) and performing a sequence of logical operations in accordance with a predetermined but variable set of procedural instructions (program) to produce a result in the form of information or signals.
a matrix obtained from a given matrix by interchanging rows and columns.
supplier
track record
tend toالمعنى
peak timesالمعنى
contract outالمعني
terms and conditionsمثال
wear and tearالمعنى
recruit
call-out
go bust
take into considerationمعناها
insurance policy
under guarantee
- The force acting in resistance to the fall is equal to 6πrηv, in which r is the radius of the sphere, η is the viscosity of the liquid, and v is the velocity of fall.
- The force acting downward is equal to 4/3 πr3 (ρ1 - ρ2)g, in which ρ1 is the density of the sphere, ρ2 is the density of the liquid, and g is the gravitational constant.
- At a constant velocity of fall the upward and downward forces are in balance.
- Equating the two expressions given above and solving for v therefore yields the required velocity, expressed by Stokes's law as: v = 2/9 (ρ1 - ρ2)gr2/η.
- Viscosity, property of a fluid that tends to prevent it from flowing when subjected to an applied force.
- High-viscosity fluids resist flow; low-viscosity fluids flow easily.
- The tenacity التَرَابُط أو التَمَاسُك with which a moving layer of fluid dragsتسحب adjacent layers الطبقات المجاورة of fluid along with it determines its viscosity.
- The rate at which the fluid flows through the orifice فتحة أو فُوَّهة is a measure of its viscosity.
هي خاصية للمادة تتسبب في وجود قوى مقاومة أو احتكاك بين طبقات السائل تعيق انزلاقها فوق بعضها البعض
أولاً : توجد قوى احتكاك بين السطح الصلب (الزجاج مثلاً) وطبقة السائل الملاصقة له (الجلسرين مثلاً) والتي نشأت بسبب قوى الالتصاق بين جزيئات الزجاج وجزيئات الجلسرين ،حيث تعمل هذه القوى على إعاقة انسياب تلك الطبقة وتبدو ساكنة وسرعتها معدومة
ثانياً : ونتيجة لقوى التماسك بين جزيئات السائل تعمل كل طبقة على مقاومة حركة الطبقة التي فوقها لأنها أسرع منها بينما تعمل على زيادة سرعة الطبقة التي تحتها لأنها ابطأ منها ولذلك ينشأ بين طبقات السائل قوى شبيهة بقوى الاحتكاك تعيق انسياب السائل
إذا ضاقت بك الدنيا فلا تقل يا رب عندي هم كبير ولكن قل يــــا هــــــــم عندي رب كبير